Review of Scientific Reviews Relating to Water Fluoridation

Transcription

1 Review of Scientific Reviews Relating to Water Fluoridation Published between September 2011 and January 2012 National Fluoridation Information Service Review JANUARY

2 COPYRIGHT AND LICENCING Copyright National Fluoridation Information Service This document is licensed for use under the terms of Creative Commons Public License Attribution No-Commercial No Derivatives Version 3.0 ( Any use of this document other than those uses authorised under this license or copyright is prohibited. 2

3 TABLE OF CONTENTS PLAIN ENGLISH SUMMARY...5 Background and Purpose...5 The New Zealand Context...5 Method 6 Key findings...7 Key findings and implications relevant to the Ministry of Health s community water fluoridation programme INTRODUCTION Background and Purpose Ministry of Health s Current Fluoridation Policy Fluoridation of the Drinking Water Supply in New Zealand The New Zealand Context Structure of the Report METHOD Selection of Papers Critical Appraisal of Papers FINDINGS FROM THE CRITICAL APPRAISAL...15 Background on the mechanism of action of fluoride in preventing dental caries Oral and Public Health Epidemiology Review Review Review Review Review Review Review Review Review Fluoride and IQ

4 3.2 Communication and Community Engagement Review Reivew Toxicology and Pharmacology Other: Health Economics: Review APPENDICES...23 Appendix 1: Oral and Public Health Epidemiology...23 Appendix 2: Communication and Community Engagement...89 Appendix 3: Other: Health Economics Appendix 4: Toxicology and Pharmacology Appendix 5: Dean s Index Appendix 6: The Significant Caries (SiC) Index Appendix 7: Thylstrup-Fejerskov Fluorosis Index (1979) T-F Index Appendix 8: Fluorosis Risk Index (FRI) Appendix 9: Abbreviations and Acronyms

5 PLAIN ENGLISH SUMMARY Background and Purpose The Ministry of Health (the Ministry) recommends community water fluoridation (CWF) where technically feasible as a safe and effective means of improving oral health. Approximately 56% 1 of the New Zealand population currently has access to fluoridated drinking-water. The Ministry aims to increase access to CWF programmes to 70% of the population. Under current New Zealand law, District Health Boards (DHBs) are responsible for protecting the health of their populations, while local councils are charged with deciding whether to fluoridate the water supplies they operate. With water fluoridation a controversial issue, it was deemed important that District Health Boards and the Ministry have access to the best scientific evidence. The Ministry established a National Fluoridation Information Service (NFIS, the Service) to: i. Monitor public discussion and decision-making processes on CWF in New Zealand; ii. iii. iv. Provide a central authoritative, accurate and up-to-date source of information and critical commentary on research pertaining to CWF; Coordinate support, communication and clinical and technical advice to, and on behalf of, the Ministry and District Health Boards; Ensure consistent, accurate, and up-to-date information and messages are communicated by the Ministry and District Health Boards; v. Evaluate the effectiveness of the Service in advancing CWF in New Zealand. The current literature review critically appraises scientific papers published between September and December 2011, complementing previous reviews for the Service (available on the website The review identifies the implications of its findings for the Ministry s CWF fluoridation policy. The New Zealand Context Important facets of the New Zealand context in relation to CWF are: i. naturally-occurring fluoride concentrations in New Zealand s water supplies are low generally less than 0.2mg/L; ii. the maximum acceptable value for fluoride in drinking water, given in the Drinking-Water Standards for New Zealand and based on the World Health Organization Guideline, is 1.5mg/L, which is designed to prevent possible undesirable health effects that may result from excessive fluoride intake; 1 This calculation is based on the population currently on fluoridation drinking water approximately 2,272,832 (number supplied by the Ministry of Health) divided by the total New Zealand population counted in the 2006 census of 4,027,947. 5

6 iii. up-to-date information about the prevalence of tooth decay in New Zealand is available from the New Zealand Oral Health Survey 2 ; iv. the prevalence of tooth enamel defects does not appear to be increasing in New Zealand 3 ; v. toothpaste in New Zealand is fluoridated at approximately 1000mg/kg, which is typical of other developed countries, and considered safe for use by children 2. Method Papers related to water fluoridation and fluorosis were selected for review in four topic areas: i. Oral and Public Health Epidemiology; ii. iii. iv. Communication and Community Engagement; Toxicology and Pharmacology; Other: including Health Economics. Seven scientific bibliographic databases were searched for articles in the above topic areas: i. Cochrane; ii. iii. iv. Mosbys; Pubmed; INNZ; v. Ovid; vi. vii. Web of Knowledge; Scopus. Papers identified in the database searches were assessed for relevance against the following criteria: i. Available in English; ii. Primary focus on CWF health effects or impacts; iii. A new study (as opposed to an historical commentary, opinion piece or editorial); iv. Can be classified into one of subject fields noted above; v. A study of an area or country with a context comparable to New Zealand; vi. Primarily concerned with fluoride in drinking water levels within the currently recommended fluoridation range in New Zealand ( mg/L). Some papers, which were originally deemed to have some relevance to NZ CWF and that would otherwise have been rejected as not meeting the above criteria, have been reviewed these papers are indicated with an asterisk (*). A total of 358 papers were identified, but only 44 were deemed relevant for critical appraisal and are included in this review. 2 Available at: 3 Ministry of Health Guidelines for the use of fluoride Wellington. Available at 6

7 Key findings Summary of key findings The papers appraised in this review, which are relevant to New Zealand and of at least medium validity, provide no support for any change in the Ministry s current policy on CWF. The key findings were: i. There was no statistically significant association between composite water fluoridation levels (not defined) and new non-cavitated caries count or new cavitated caries count [2]. ii. Infant formula use was associated with higher prevalence of fluorosis in non-fluoridated areas but not in fluoridated areas [3]. iii. Fluoride is a caries prevention measure in rural indigenous communities [12],[29]. iv. Water fluoridation status in the continental U.S. has no influence on osteosarcoma incidence rates during childhood and adolescence [14]. v. A study in Iraq highlighted that bottled water was an influencing factor on overall fluoride consumption [17]. vi. Fluoride intake of infants from infant milk formulas depends on the fluoride concentration of added water [21]. vii. In a low-fluoride community, developmental defects of enamel were twice as common in the permanent dentition versus the primary dentition [26] viii. In Santiago, Chile, any increase in fluorosis severity for 6-8- and 12-year old children is accepted as a reasonable consequence and of minor importance, given the substantial protection against dental caries provided by drinking water containing an optimal fluoride concentration [33]. ix. Increasing public knowledge and understanding of fluoride reduces public concern about CWF and improves oral health behaviours [35],[36]. x. In the USA, CWF represents a cost effective method of reducing dental caries in children from less well-off families who qualify for subsidised dental care [41]. 7

8 Key findings and implications relevant to the Ministry of Health s community water fluoridation programme Nine papers in Oral and Public Health Epidemiology were assessed to be relevant to the Ministry s CWF policy and of acceptable validity (medium to high). Chankanka, et al., (2011)[2] using data from the Iowa Fluoride Study, found no statistically significant association between composite water fluoridation levels (not defined) and new noncavitated caries count or new cavitated caries count. Whilst this was a prospective, longitudinal study covering primary, mixed and permanent dentition, the 156 study subjects were predominantly from white high socioeconomic status families and had low caries prevalence and there was no control for the effects of factors such as dental insurance, dental preventative services, nonbeverage dietary factors, parental behavioural factors and parental caries experience. Two studies examined the relationship between infant formula feeding and oral health. In a study based in South Australia, Do, Levy and Spencer (2011)[3] found that infant formula use was associated with higher prevalence of fluorosis in non-fluoridated areas but not in fluoridated areas. The type of water used for reconstituting infant formula in fluoridated areas was associated with caries experience. A laboratory based study by Nohno, Zohoori and Maguire (2011)[21] measured the fluoride content of all infant milk formulas available for purchase in Japan and estimated the fluoride exposure of infants whose primary source of nutrition was infant milk formulas when reconstituted with different fluoride concentrations of water. This study was based on modelling of fluoride intake using guidelines provided on the formula and calculating milligrams fluoride per kilogram body weight. The results suggested that fluoride intake of infants from infant milk formulas depended on the fluoride concentration of added water. Therefore, the risk of dental fluorosis for most Japanese infants would be small as most Japanese municipal water supplies are low in fluoride. Two studies showed that fluoride is a caries prevention measure in rural indigenous communities. Klejka, et al., (2011)[12], in a study of five Alaskan communities (two with fluoridated water and three without), found the prevalence of caries was lower in communities with CWF. In addition, the level of soda pop consumption was positively associated with number of dmft/ DMFT. Slade, et al., (2011)[29] found that CWF had a statistically significant impact, independent of a fluoride varnish and the oral health promotion programme, the intervention, on the number of decayed, missing and filled (primary tooth) surfaces (dmfs), by on average 4.3 carious surfaces per child in Aboriginal communities in the Northern Territory of Australia, where dental caries disease is endemic. Levy and LeClerc (2011)[14] conducted an ecological analysis on the relationship between fluoride in drinking water and osteosarcoma in children and adolescents in the USA. The authors concluded that: Our ecological analysis suggests that the water fluoridation status in the continental U.S. has no influence on osteosarcoma incidence rates during childhood and adolescence. 8

9 Matloob (2011)[17] found that the fluoride concentration in bottled water in Iraq was well below concentrations required for caries preventation. The study concluded that low levels of fluoride in both tap and bottled water resulted in below optimal protection against dental caries in Iraq. Whilst the study was conducted in Iraq it has some relevance to New Zealand by highlighting that bottled water has an influencing factor on overall fluoride consumption. Since 2009 in Australia and New Zealand, fluoride is permitted to be added to bottled water up to mg/L. If fluoride is added this must be stated on the label) 4 The Australian study by Seow, et al., (2011)[26] compared developmental defects of enamel (DDE) in the primary and permanent dentitions of 517 children from a low-fluoride district. They found that developmental defects of enamel were twice as common in the permanent dentition versus the primary dentition. In the primary dentition, the predominant defects were demarcated opacities and missing enamel, while in the permanent dentition, the defects were more variable. The prevalence rate of diffuse opacities of approximately 49% in permanent dentition was similar to that observed in communities with levels of optimally fluoridated water of approximately 0.7 to 1ppm. The authors suggested that the children in the study may have consumed other sources of systemic fluoride, such as toothpaste or foods and beverages manufactured using fluoridated water. Yevenes, et al., (2011)[33] conducted a study to assess the damage and the prevalence of caries and fluorosis in children and adolescents in Santiago, Chile 8 years after the introduction of drinking water fluoridation to the city and to compare them with the baseline study. The study found the number of children with no history of caries had increased by approximately 100% and the number of cases significantly affected by caries had decreased significantly. The incidence of dental fluorosis has increased, but to milder degrees. While the study has some limitations (eg, it does not control for changes in use of other sources of fluoride) it provides support for CWF as an effective means of caries prevention. Two papers classified as Communications and Community Engagement were found to be both of acceptable validity and relevant to the Ministry s CWF policy. Furukawa, et al., (2011)[35] conducted a study in Japan, examining support for and concern about CWF. The authors concluded that increased knowledge of and experience with fluoride might help decrease the perception of risk and increase motivation for implementing water fluoridation among the general public. Jensen, et al., (2011)[36] conducted a study on tooth-brushing behaviours and use of fluoride toothpastes in different age groups in Sweden. The study found that factors which increased the odds for having good caries-preventive behaviour were: (i) being female, (ii) being younger than 35 years old, (iii) having knowledge about fluoride, (iv) finding use of fluoride toothpaste important and (v) rating one s own oral health as good. The authors concluded there was greater potential for improvement in the techniques for using fluoride toothpaste effectively, among the older respondents

10 One of the Other: Health Economics papers was of acceptable validity and relevance to the Ministry s CWF policy. Lopez (2011)[41] conducted a cost effectiveness analysis of CWF for children on the Medicaid STEPS programme in the USA. He found that CWF had a cost saving effect that would repay the implementation and maintenance of CWF within 2-7 years. While the study has some limitations regarding the data it used, it does support CWF as a cost effective method of improving the oral health of children from low socio economic backgrounds, which is a key target of Ministry s policy on CWF. 10

11 1 INTRODUCTION 1.1 Background and Purpose Epidemiological studies in the first half of the 20th century showed that naturally-occurring fluoride in water could be beneficial (i.e. reduce dental caries disease) and detrimental (fluorosis) to dental health 5. Work to find the fluoride concentration that offered an acceptable balance between these effects eventually led to the introduction of fluoride into drinking-water supplies as a public health measure in the USA and Canada in the mid 1940 s 5. Fluoride was first added to the Hastings drinking-water supply in New Zealand in The fluoridation of water supplies in New Zealand expanded rapidly during the 1960 s 6. The Ministry s Annual Review of Drinking-water Quality 2008/ states that 51 drinking-water treatment plants in New Zealand added fluoride to their water. These treatment plants provided water to just about 2.25 million people approximately 52% of the New Zealand population. The Ministry aims to raise the percentage of New Zealanders receiving fluoridated water to 70% 8. Under current legislation, local authorities hold the mandate to decide whether water supplies in their jurisdictions are fluoridated. Debate concerning the pros and cons of water fluoridation continues, with the fluoridation status of water supplies changing as the positions of councils and their communities on the issue shift. To advance water fluoridation in New Zealand by ensuring that debates on fluoridation are based on the best available scientific evidence, the Ministry established a National Water Information Service (NFIS, the Service) to: i. Provide a central authoritative, accurate and up-to-date source of information and critical commentary on research pertaining to water fluoridation ii. iii. iv. Provide coordinated clinical and technical support and advice to DHBs, TLAs and the MoH Ensure DHBs and the MoH are able to communicate consistent, accurate and up to date information on water fluoridation Follow public discussion and decision making on water fluoridation v. This literature review provides a critical appraisal of research papers published in a variety of sources between September and December It complements previous literature reviews available at the Service website, 5 Parnell C, Whelton H, O Mullane D Water Fluoridation. European Archives of Paediatric Dentistry; 10: accessed 21 January accessed 17 January

12 1.2 Ministry of Health s Current Fluoridation Policy An important function of this review is to identify the implications of the findings for the Ministry s current policy on CWF, and where necessary to propose changes to the policy. At present, the Ministry s policy focuses on the concentration of fluoride that is required in drinkingwater to achieve the desired health outcomes. It is summarised in a statement approved by the Ministry s Executive Leadership Team 9 as: The Ministry of Health recommends the adjustment of fluoride to between 0.7ppm and 1.0ppm in drinking-water as the most effective and efficient way of preventing dental caries in communities receiving a reticulated water supply, and strongly recommends the continuation and extension of water fluoridation programmes where technically feasible. 1.3 Fluoridation of the Drinking Water Supply in New Zealand The Drinking-water Standards for New Zealand 2005 (revised 2008) (DWSNZ) give the maximum acceptable value (MAV) for the concentration of fluoride in drinking-water as 1.5mg/L. The purpose of the MAV is to prevent possible undesirable health effects that may result from excessive fluoride intake. This should not be confused with the recommended concentration range for fluoride contained within the Ministry s fluoridation policy. Although the recommended fluoride concentration range is below the MAV, it straddles 50% of the MAV which has implications for fluoride monitoring for compliance with the DWSNZ. To comply with the DWSNZ, all chemical determinants at concentrations exceeding 50% of their MAV within a water supply must be monitored on a regular basis. As fluoridating water treatment plants aim to add fluoride to achieve a concentration in the range of mg/L (cf. 50% of the MAV being 0.75mg/L), treatment plants are required to test the fluoride concentration in the water they produce at least weekly to comply with the DWSNZ. They are likely to determine the fluoride concentration in their water supply on a more frequent basis because of the relatively small difference between a therapeutic fluoride concentration and the fluoride MAV. The Ministry s Annual Review of Drinking-water Quality 2009/ reported that 48 treatment plants monitor for fluoride, providing water to approximately 2,352,000 people in 122 distribution zones. No fluoridating treatment plant recorded a fluoride concentration exceeding its MAV for this reporting period. 1.4 The New Zealand Context Two important factors that can influence the extent to which individuals are exposed to fluoride in the absence of an intentionally-fluoridated water supply are naturally-occurring levels of fluoride in the water and the use of fluoridated toothpaste. To contextualise the conclusions reached in this literature review, the levels of fluoride in these potential fluoride sources are discussed here. 9 Personal communication., Corinne Thomson, Ministry of Health, 22 November

13 With the exception of geothermally-influenced waters, which are not used as the source waters of community water supplies, naturally-occurring fluoride levels in New Zealand waters are low, certainly by the standards of many other countries. Davies et al. 10 (2001) reported a fluoride concentration range from nd (not detectable, reported as 0.1 or 0.2mg/L) to 1.8mg/L, with a median concentration of nd in New Zealand drinking-water supplies. Only three drinking-water supplies showed a fluoride concentration greater than 0.75mg/L (50% of the MAV). Consequently, some of the findings relating to overseas jurisdictions in which fluoride may occur naturally at concentrations of many mg/l will not apply to New Zealand. The Ministry of Health reports that the concentration of fluoride in most New Zealand toothpastes is around 1000ppm (parts per million) 11, which is considered safe for children. This concentration is typical of the concentrations contained in toothpaste in developed countries, and findings associated with the use of fluoridated toothpaste in these countries may also be relevant to New Zealand. Toothpaste marketed for children less than six years of age is available with a fluoride content of 400ppm (though this is not recommended by the Ministry of Health 12. One further factor to be considered in association with overseas reports of increasing levels of dental fluorosis is the evidence of trends in fluorosis in New Zealand. The Ministry s Guidelines for the use of fluoride 3 states that the prevalence of diffuse opacities has not increased compared to earlier studies and is largely unchanged from estimates reported within New Zealand over the last 25 years. On this basis, trends of increasing fluorosis reported in overseas jurisdictions with fluoridated water supplies do not necessarily reflect the New Zealand context. 1.5 Structure of the Report Following the introduction, the report describes the method used to identify papers for inclusion in the review. The following discussion of the findings from the papers, which includes a summary of key points, is the basis for a discussion about implications for the Ministry s CWF policy, and proposals relating to fluoridation policy. The main body of the report closes with a presentation of possible research directions derived from the papers. The Appendix has the critical appraisals of the 44 papers and abstracts. It includes the bibliographic details, as well as a summary of the study s key findings linked, where possible, to the New Zealand CWF context, an evaluation of the quality of the study and level of evidence it provides, together with comments on the implications for the Ministry s CWF policy. 10 Davies H, Nokes C, Ritchie J A Report on the Chemical Quality of New Zealand s Community Drinkingwater Supplies. ESR Report FW0120 to the Ministry of Health

14 2 METHOD 2.1 Selection of Papers A comprehensive search of several scientific bibliographic databases was carried out on a monthly basis to identify academic peer-reviewed papers that might meet the requirements for inclusion in the literature review. Ministry of Health Library staff identified papers from Cochrane, Mosbys, Pubmed, INNZ and Ovid databases using key words: water fluoridation, water fluorid* and fluorosis. Scopus and Web of Knowledge databases were also searched, using the same search parameters, by Massey University staff. The target publications were research papers published between September 2011 and December 2011 reporting scientific studies concerning water fluoridation and the health effects of water fluoridation that might arise in conjunction with topical application of fluoride (for example, the use of fluoridated toothpaste, fluoride varnish). The subject areas of interest were: oral and public health epidemiology, public health policy, communication and community engagement, toxicology and pharmacology and other. The titles and abstracts of 358 papers identified through these initial searches were reviewed, and papers and abstracts were accepted if the following criteria were met: i. Available in English; ii. iii. iv. Primarily concerned with water fluoridation at levels relevant to optimal water fluoridation levels ( mg/l) currently recommended in New Zealand, or contained a major segment relevant to water fluoridation; A report of a scientific study, not a review of studies, a commentary, opinion piece or editorial; The subject of the paper or abstract fell into one of the four subject areas specified by Ministry (i.e.: Oral and Public Health Epidemiology, Communication and Community Engagement; Toxicology and Pharmacology; v. Reported a population study in an area or country in which the context was similar to that of New Zealand. Some papers, which were originally deemed to have some relevance to NZ CWF and that would otherwise have been rejected as not meeting the above criteria, have been reviewed, these papers are indicated with an asterisk (*). A total of 358 papers were identified, of which 44 were deemed relevant for critical review. 2.2 Critical Appraisal of Papers The papers in the Appendix were critically appraised using uniform criteria. 14

15 3 FINDINGS FROM THE CRITICAL APPRAISAL This section presents the key findings of the papers reviewed. The following subject areas were covered: i. Oral and Public Health Epidemiology associated with water fluoridation; ii. iii. iv. Communication and Community Engagement; Toxicology and Pharmacology; Other: including Health Economics. The Appendix has the critical appraisals of the 44 papers and abstracts. Each paper is numbered to allow indexing in the main body of the report (in square brackets). Each entry includes the bibliographic details, as well as a summary of the study s key findings linked, where possible, to the New Zealand CWF context, an evaluation of the quality of the study and level of evidence it provides, together with comments on the implications for the Ministry s CWF policy. Knowing the validity of the findings of a study is critical for understanding the study s implications. The reviewers notes in the Appendix assessed the quality of each paper. Papers of poor quality, although reviewed are not discussed in Section 3. Their reviews, including the reviewer s reasons for considering the paper to be of unacceptable quality, are contained in the Appendix. The Validity and Relevance of each paper are highlighted in this section. Papers which major methodological issues (for example low sample size, lack of control for confounding factors, poorly reported or lack of supporting data) were considered of low validity and therefore excluded from this section of the review. Findings from low validity papers are not included in the summary of the key findings from relevant papers (sections 3.1, 3.2, 3.3, 3.4) but the critical appraisal is included in the Appendix. Background on the mechanism of action of fluoride in preventing dental caries It is generally accepted that the main actions by which fluoride acts to protect dental enamel are through remineralisation and the inhibition of demineralisation 13. Exposure of the enamel surface of the post-eruptive tooth (a tooth exposed through the gum) to fluoride is of greatest importance in creating a surface resistant to acids formed by bacteria. The beneficial effects of the post-eruptive interaction of fluoride with teeth have been well demonstrated by epidemiological studies. A constant low level of fluoride in the oral cavity assists the post-eruptive protective mechanism 14. The application of fluoride to the surface of the tooth to improve its resistance to caries, by using toothpaste or fluoride varnish, is termed topical application. 13 Kumar JV Is water fluoridation still necessary? Advances in Dental Research; 20: Levy SM An update on fluorides and fluorosis. Journal of the Canadian Dental Association; 69:

16 The ingestion of fluoride is a means by which fluoride can gain access to the pre-eruptive tooth (i.e. prior to the tooth being exposed through the gum). This is termed systemic application. Although the post-eruptive effect of fluoride is well accepted, the pre-eruptive effects of fluoride on the tooth, and the extent to which this influences resistance to caries is still under debate. CWF provides a mechanism by which fluoride can reach the tooth both topically and systemically. In particular it provides a means by which a constant low level of fluoride can be sustained in the oral cavity. Evaluating the relative contributions of the pre- and post- eruptive action of fluoride is extremely difficult, but irrespective of their relative importance, fluoridated water helps to ensure constant exposure to low concentrations of fluoride. Excessive exposure of the tooth to fluoride during the pre-eruptive stage of enamel formation causes hypomineralisation 15 of the enamel, known as enamel fluorosis. 3.1 Oral and Public Health Epidemiology Review 2 Chankanka et al., (2011)[2] used data from the Iowa Fluoride Study to assess the longitudinal associations between caries outcomes and modifiable risk factors. No statistically significant association was found between composite water fluoridation levels (not defined) and new noncavitated caries count or new cavitated caries count. Whilst this was a prospective, longitudinal study covering primary, mixed and permanent dentition, the 156 study subjects were predominantly from white high socioeconomic status families and had low caries prevalence and there was no control for the effects of factors such as dental insurance, dental preventative services, nonbeverage dietary factors, parental behavioural factors and parental caries experience. Validity and Relevance of Chankanka et al., (2011) This study is of medium validity The study is of relevance to the Ministry s CWF policy as it suggests composite water fluoridation levels have no statistically significantly impact on dental caries count among medium to high socioeconomic status children, who have low to moderate caries experience Review 3 The objective of the study by Do, Levy and Spencer (2011)[3] was to evaluate associations between patterns of infant formula feeding and dental fluorosis and caries in a representative sample of 588 Australian children aged 8-13 years. The participants were examined for dental fluorosis, information on caries experienced at 8-9 years was extracted from their dental records and a parental questionnaire provided data on infant feeding patterns. The study found that use of infant 15 Hypomineralisation is a deficiency of minerals (in particular calcium) in the tooth enamel 16

17 formula for more than 6 months in non-cwf areas increased the risk of dental fluorosis. No increase in dental fluorosis was found with use of infant formula in CWF areas. The type of water used for reconstituting infant formula in fluoridated areas was associated with caries experience Validity and Relevance of Do, Levy and Spencer (2011) This study is of medium validity. This study is of relevance to the Ministry s CWF policy. No statistically significant increase in dental fluorosis was found with use of infant formula in CWF areas Review 21 The study by Nohno, Zohoori and Maguire (2011)[21] aimed to measure the fluoride content of all infant milk formulas available for purchase in Japan and estimated the fluoride exposure of infants whose primary source of nutrition was infant milk formulas when reconstituted with different fluoride concentrations of water. It was based on 22 brands of infant formula from six manufacturers under laboratory conditions and included modelling of fluoride intake using guidelines provided on the formula and calculating milligrams fluoride per kilogram body weight. The results suggested that fluoride intake of infants from infant milk formulas depended on the fluoride concentration of added water. Therefore, the risk of dental fluorosis for most Japanese infants would be small as most Japanese municipal water supplies are low in fluoride. Validity and relevance of Nohno, Zohoori and Maguire (2011) This study is of medium validity The study is of relevance to the Ministry s CWF policy as it provides advice on baby formula use in fluoridated and non fluoridated water areas to ensure baby formula fluoride content is kept a Review 17 The study by Matloob (2011)[17] evaluated the fluoride content of tap and bottled water currently consumed in Babil Governorate Iraq to determine whether fluoride intakes by Iraqi consumers fell within the recommended ranges. Fluoride concentrations of 50 samples of tap water (originating from the Euphrates River) and forty popular brands of bottled water currently sold in Babil-Iraq were determined. The mean fluoride content of tap and bottled water were 0.184±0.041 and 0.073±0.066mgL-1, respectively. The fluoride concentration of Babil s tap water, ranged from to 0.260mgL-1, levels considered by the World Health Organisation (WHO) as insufficient to prevent caries. The authors concluded that the levels of fluoride in tap or bottled water used as the primary source of drinking water put Iraqi consumers are at a higher risk of tooth decay. Community water fluoridation is recommended as a relevant public health measure to increase the resistance to dental caries. 17

18 Validity and relevance of Matoob (2011) This study is of medium validity. This study is of relevance to the Ministry s CWF policy as although the Iraqi context is very different from New Zealand, it indicates the consumption of bottled water as influencing the effectiveness of CWF Review 12 Klejka et al., (2011)[12], investigated dental caries and associated risk factors of dental caries in five remote Alaskan villages, two with fluoridated drinking water supplies and three without. The authors found the prevalence of caries was lower in communities with CWF. Children from villages without water fluoridation had 57-91% one or more missing, filled or decayed tooth compared to 31-91% of those with fluoridated water. In addition, the level of soda pop consumption was positively associated with number of dmft/ DMFT. Validity and relevance points of Klejka et al., (2011) The study is of medium validity. The study is of relevance to the Ministry s CWF as it provides further evidence that water fluoridation is an effective means of controlling dental caries in indigenous rural communities with limited access to dental care Review 29 Slade et al., (2011)[29] undertook a study of dental caries in Aboriginal communities in the Northern Territory of Australia. The two year prospective, cluster-randomized, concurrent controlled, open trial compared the dental health program to no such program, 30 communities were allocated at random to intervention and control groups. Twice per year for 2 years in the 15 intervention communities, fluoride varnish was applied to children's teeth, water consumption and daily tooth cleaning with toothpaste were advocated, dental health was promoted in community settings, and primary health care workers were trained in preventive dental care. Data from dental examinations at baseline and after two years were used to compute net dental caries increment per child (dmfs). Water fluoridation had a statistically significant impact on the number of dmfs that was independent of the intervention. An increase of 1ppm F in drinking water was associated with an average reduction of 4.3 carious surfaces, per child. As the authors noted: although that is an observed association, not a finding from a randomized treatment allocation, the implication is that a nonfluoridated community that adopted this intervention and increased concentration of fluoride in its water supply to 1ppm F could expect an average reduction of = 7.8 fewer carious surfaces, per child more than halving the caries rate. 18

19 Validity and relevance of Slade et al., (2011) This study is of medium validity. The study is of relevance to the Ministry s CWF as the findings support water fluoridation as a method of reducing dental caries, both in concurrence with and independent of other interventions, in rural indigenous communities Review 14 Levy and LeClerc (2011)[14] carried out an ecological analysis of the relationship between fluoride in drinking water and osteosarcoma in children and adolescents in the USA, using two cancer databases (CDC Wonder: and SEER: ). It found no sex specific statistical difference in cancer rates between males and females in younger age groups (5-9, 10-14). Sex and age specific incidence rates of osteosarcoma were similar in both high (>85% of the population have access to fluoridated water) and low (<30% of the population have access to fluoridated water) CWF state categories. There was a statistically significant higher risk of osteosarcoma for males in the age group compared to other age and gender groups, but this was not associated with state CWF status. The authors concluded that their ecological analysis suggests that the water fluoridation status in the continental U.S has no influence on osteosarcoma incidence rates during childhood and adolescence. Validity and relevance of Levy and LeClerc (2011) This study is of medium validity. This ecological study is of relevance to the Ministry s CWF as it indicates no link between CWF and osteosarcoma in children and adolescents. The authors stated that: Our ecological analysis suggests that the water fluoridation status in the continental U.S. has no influence on osteosarcoma incidence rates during childhood and adolescence Review 26 The Australian study by Seow et al., (2011)[26] compared developmental defects of enamel (DDE) in the primary and permanent dentitions of 517 healthy children from a low-fluoride district. They found that developmental defects of enamel were twice as common in the permanent dentition versus the primary dentition. In the primary dentition, the predominant defects were demarcated opacities and missing enamel, while in the permanent dentition, the defects were more variable. It was concluded that in a low-fluoride community, developmental defects of enamel were twice as common in the permanent dentition versus the primary dentition. The authors suggested that the children in their study may have consumed other sources of systemic fluoride, such as toothpaste or foods and beverages manufactured using fluoridated water. 19

20 Validity and relevance of Seow et al., (2011) This study is of medium validity. The study is of relevance to the Ministry s CWF policy as the authors suggested reasons other than water fluoride content for the presence of opacities (eg, fluoride from food and beverages or swallowing toothpaste, illness or infection (including treatments with certain antibiotics) during the tooth development stage Review 33 Yevenes et al., (2011)[33] conducted a prevalence study to assess the damage and the prevalence of caries and fluorosis in children and adolescents in Santiago, Chile 8 years after the introduction of community water fluoridation and to compare them with the baseline study. The study found the number of children with no history of caries had increased by approximately 100% and the number of cases significantly affected by caries had decreased significantly. The incidence of dental fluorosis had increased, but to milder degrees. There was a statistically significant higher rate of dental caries in the lower socioeconomic groups studied. Only 20.9% of 6-8 year olds and 20.3% of 12 year olds were caries free in the low socio economic group compared to 31.9% and 33.3% in the high socioeconomic group. The authors concluded: the resulting increase in fluorosis severity for both studied age groups is generally accepted as a reasonable consequence and of minor importance, given the substantial protection against dental caries provided by drinking water containing an optimal fluoride concentration. Validity and relevance of Yevenes et al., (2011) This study is of medium validity Despite some methodological limitations, the study is of relevance to the Ministry s CWF policy by providing further evidence that water fluoridation reduces dental caries in children. It also shows that the rate of dental caries varies by socioeconomic groups Fluoride and IQ Three studies related to the impact of fluoride on IQ [5],[24], [27] are included in Appendix 1 of this report. These were not included in the main body of the report as all are of low validity for the following reasons: none represent a similar situation to New Zealand as all were conducted in areas with naturally high water fluoride concentrations (above those used in CWF), results were not consistent either within or between studies and none of the studies controlled for confounding factors such as parental education, socioeconomic status, nutritional status and other environmental influences (for example lead and arsenic in the soil). 20

21 3.2 Communication and Community Engagement Review 35 Furukawa et al., (2011)[35] conducted a study in Japan examining support for and concern about CWF. This cross sectional study involved a questionnaire survey of 573 mothers with 2-3 year old children in Gunma prefecture. The study found that motivation (support) for water fluoridation was (statistically) significantly higher amongst those who understood the effectiveness of fluoride, those who used fluoride toothpaste and those whose children had received a fluoride application at the dentist. Knowledge of the role of fluoride in preventing caries (95.3%) was much greater than knowledge of water fluoridation (47.3%). The study suggested that: Providing direct information about water fluoridation and sampling a cup of fluoridated water may therefore have important roles in decreasing the perception of dread risk and unknown risk in residents. Validity and relevance of Furukawa et al., (2011) The study is of medium validity. The study is of relevance to the Ministry s CWF policy as it supports oral health promotion initiatives to increase public knowledge and understanding of fluoride as a means of addressing concerns regarding CWF Review 36 Jensen et al., (2011)[36] conducted a study examining the use of fluoride toothpastes and tooth brushing habits amongst different age groups in Sweden. The participants were selected from the population register by random selection of birth dates and questionnaires sent to 3200 individuals aged years. The response rate was 63%. Good toothpaste behaviour identified as brushing at least twice a day, using at least 1cm toothpaste, brushing 2 minutes or longer and using a small amount of water when rinsing was reported by only 10% of the respondents. The factors that increased the odds for having good caries-preventive behaviour were: (i) being female, (ii) being younger than 35 years, (iii) having knowledge about fluoride, (iv) finding use of fluoride toothpaste important and (v) rating one s own oral health as good. The study found there was great potential for improving the techniques for using fluoride toothpaste effectively, especially among the older participants. Validity and relevance of Jensen et. al. (2011) This study is of medium validity. This study is of relevance to the Ministry s CWF policy as it supports promotion of the caries preventative effects of fluoride to improve oral health behaviour. 21

22 3.3 Toxicology and Pharmacology None of the papers accessed under the heading Toxicology and Pharmacology were relevant to the 3.4 Other: Health Economics: Review 41 Lopez (2011)[41] conducted a cost effectiveness analysis of CWF for children on the Medicaid STEPS programme in Texas, USA. He calculated that CWF provided a cost saving to the STEPS programme of $18-20 per child per year. This represented a 16 percent reduction in Medicaid dental treatment costs. Using these figures, it was found that the cost of installing and maintaining water fluoridation infrastructure would be recouped in 2-7 years. However, Medicaid is limited to low socioeconomic status children, and therefore findings can only be generalised to this population subgroup. In addition, the ecological data used in the study was collected between 1997 and 1999 so may not reflect recent trends in oral health. Validity and relevance of Lopez (2011): The study is of low validity due to the limitations stated above. The study is of relevance to the Ministry s CWF policy by indicating that CWF provides a cost saving to publicly funded dental health services where applied to children from low socioeconomic backgrounds. 22

23 APPENDICES Appendix 1: Oral and Public Health Epidemiology [1] Date: November 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: The prevalence of molar incisor hypomineralisation in Northern England and its relationship to socioeconomic status and water fluoridation. Balmer R, Toumba J, Godson J, Duggal M International Journal of Paediatric Dentistry (4) Oral and Public Health Epidemiology Background. Molar incisor hypomineralisation (MIH) is a condition which has significant implications for patients and service provision. Aims. The aim of this survey was to determine the prevalence of MIH in 12-year olds in Northern England and to consider the relationship with socioeconomic status and background water fluoridation. Design. Twelve-year-old children were examined for the presence of MIH. Participating dentists were trained and calibrated in the use of the modified Developmental Defects of Enamel index. Children were examined at school under direct vision with the aid of a dental mirror. A diagnosis of MIH was attributed to a child if they had a demarcated defect in one or more of their first permanent molars. Results. Of 4795 children that were selected, 3233 (67.4%) were examined. Overall prevalence of MIH was 15.9% ( %). There was an association between prevalence of MIH and deprivation quintiles with a positive correlation in the first 4 quintiles (P<0.05). There was no difference in prevalence between fluoridated Newcastle and other areas. Conclusion. Prevalence of MIH is equivalent to other European populations. Prevalence was related to socioeconomic status but not to background water fluoridation. Study Location: Study Dates: Type of Study: North of England Prevalence Study Validity of Study: Low Key Points: The only area with water fluoridation in this study (Newcastle), had a statistically significant lower rate of MIH (10.8%) compared to the other areas included in the study (17.4%). Newcastle also had higher rates of diffuse defects to teeth (associated with dental fluorosis) (8.7%) compared to other areas studies (3.3%). MIH increased between socioeconomic status Quintiles 1-4 (i.e. from low SES to high SES) but decreased in Quintile 5. This difference was statistically significant and had not been seen in other studies. Water fluoridation does not increase the prevalence of hypomineralisation and may reduce it (authors suggested through remineralisation of teeth by topical fluoride exposure). Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? FAIR GOOD 23

24 Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Schools were selected randomly and participants within schools stratified. Inter examiner calibration was undertaken with the Kappa index indicating good to excellent level of consistency. Individual level study. Good response rate (67.4%) Limitations: Some self-selection may have occurred as parental permission was required and inclusion was dependent on attendance on specified date. Can the findings be generalised? - limited Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Ecological data used to determine level of deprivation (by matching child s postcode to deprivation index quintile) The authors noted that the ideal age for this study would have been 7-8 years, as by 12 years some of the children had first molars missing and other teeth had to be substituted. Other studies have demonstrated that MIH leads to increased extraction of tooth. A major limitation is that the authors got the association reversed see figure 1 The authors didn t state if those children (n=1562) who didn t participate (parents decline or children were absent) were different from those who did Study reports on the prevalence of a condition which was initiated 12 years previously (ie, at birth). During that period, aspects of the demographics may have changed (eg, socioeconomic status). No data was included on time at residence since birth Part of the study was conducted in an area with high fluoride : limited only as an indicator perhaps there are deficiencies in the study to say it was of low validity. Some indication from study that water fluoridation does not increase the risk of MIH, but may increase the risk of mild fluorosis. 24

25 [2] Date: January 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Study type: Location of Study: Time of Study: Validity of Study: Key Points: Longitudinal associations between children s dental caries and risk factors Chankanka O, Cavanaugh JE, Levy SM, Marshall TA, Warren JJ, BroffittB, Kolker JL Journal of Public Health Dentistry Oral and Public Health Epidemiology Dental caries is a common disease in children of all ages. It is desirable to know whether children with primary, mixed, and permanent dentitions share risk factors for cavitated and non-cavitated caries. Objective: To assess the longitudinal associations between caries outcomes and modifiable risk factors. Methods: One hundred and fifty-six children in the Iowa Fluoride Study met inclusion criteria of three dental examinations and caries-related risk factor assessments preceding each examination. Surface-specific counts of new noncavitated caries and cavitated caries at the primary (Exam 1: age 5), mixed (Exam 2: age 9) and permanent (Exam 3: age 13) dentition examinations were outcome variables. Explanatory variables were caries-related factors, including averaged beverage exposure frequencies, tooth brushing frequencies, and composite water fluoride levels collected from 3-5, 6-8, and years, dentition category, socioeconomic status, and gender. Generalized linear mixed models (GLMMs) were used to explore the relationships between new noncavitated or cavitated caries and caries-related variables. Results: Greater frequency of 100 percent juice exposure was significantly associated with fewer non-cavitated and cavitated caries surfaces. Greater tooth brushing frequency and high socioeconomic status (SES) were significantly associated with fewer new non-cavitated caries. Children had significantly more new cavitated caries surfaces at the mixed dentition examination than at the primary and permanent dentition examinations. Conclusions: There were common caries-related factors for more new non-cavitated caries across the three exams, including less frequent 100 percent juice exposure, lower tooth brushing frequency and lower SES. Less frequent 100 percent juice exposures might be associated with higher exposures to several other cariogenic beverages. Longitudinal Study Iowa, USA Medium Participants were recruited at birth from eight Iowa hospital post-partum units and had to have remained in the study for years and three dental examinations. Composite water fluoride levels (not defined) were not statistically significantly associated with new non-cavitated caries count or new cavitated caries count Increase tooth brushing frequency was statistically significantly associated with fewer new non-cavitated and cavitated caries counts Higher socio economic status was statistically significantly associated with fewer non cavitated caries count Lowest cavitated caries were found at the third examination (of permanent teeth) this was suggested to be due to a shorter time period since the eruption of the teeth and a change in preventative methods, including home fluoride use (in toothpastes, mouthwashes etc.) Composite water fluoride levels were lower for older children, possibly due to increased use of bottled water Evaluation Criterion: 25

26 The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD Strengths: Prospective, longitudinal study since birth. Extensive data collection on: water fluoride exposure, diet, socio economic status and oral health behaviour as well as caries outcomes on primary, mixed and permanent dentition. Composite water fluoride levels, beverage consumption (powdered beverages, sugared soda pop, juice drinks, 100% juice, milk and water), tooth brushing, socio economic status and gender were each tested against new cavitated and non-cavitated caries separately with all other listed variables controlled for. Used mixed modelling approach which considers fixed and random effects Limitations: The cohort had an above average proportion of high and middle socio economic status participants, (37.8% and 34.1% respectively). Almost all subjects were white and most had low to moderate levels of caries. Dental insurance, dental preventative services, non-beverage dietary factors, parental behavioural factors and parental caries experience were not controlled for. Can the findings be generalised? Limited to cohorts with the characteristics stated: white, middle-high socio economic status with low to moderate caries incidence. Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Indicates composite water fluoride levels had no statistically significant impact in caries count. See above. May require further study in a New Zealand context 26

27 [3] Date: November 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Association between infant formula feeding and dental fluorosis and caries in Australian children Do LG, Levy S, Spencer AJ Journal of Public Health Dentistry Oral and Public Health Epidemiology Objective: The objective of this study was to evaluate associations between patterns of infant formula feeding and dental fluorosis and caries in a representative sample of Australian children. Methods: A population-based study gathered information on fluoride exposure in early childhood. Information on infant formula feeding and fluoridation status was used to group children: three groups in non-fluoridated areas (formula nonuser, user for 6 months, and user for 6+ months) and four groups in fluoridated areas (nonuser, user with non-fluoridated water, user with fluoridated water for 6 months and user with fluoridated water for 6+ months). Children aged 8-13 years were examined for fluorosis using the Thylstrup and Fejerskov (TF) Index. Primary tooth caries experience recorded at age 8-9 years was extracted from clinical records. Fluorosis cases were defined as having TF 1+ on maxillary incisors. Fluorosis prevalence and primary caries experience were compared across formula user groups in multivariable regression models adjusting for other factors. Results: Total sample was 588 children. Children in fluoridated areas had higher prevalence of very mild to mild fluorosis, but lower caries experience than those in non-fluoridated areas. Among children in non-fluoridated areas, formula users for 6+ months had significantly higher prevalence of fluorosis compared with nonusers. There was no significant difference in fluorosis prevalence among the formula users in fluoridated areas. Among children in fluoridated areas, formula users with non-tap water had higher caries experience. Conclusion: Infant formula use was associated with higher prevalence of fluorosis in nonfluoridated areas but not in fluoridated areas. Type of water used for reconstituting infant formula in fluoridated areas was associated with caries experience. Study Location: Study Dates: Type of Study: South Australia Population based nested case control study Validity of Study: Medium Key Points: Children who lived their first year of life in fluoridated area had higher rates of dental fluorosis (32%) than those in non-fluoridated areas (20%). Most children with dental fluorosis had it to either a very mild or mild degree; only 2% had level 3 (moderate) and none had fluorosis above this level. Children from non-fluoridated areas who were fed milk formula as infants for 6+ months had higher rates of dental fluorosis (31%) than those that were not fed formula (16%). However, for those fed formula for less than 6 months the rate was very similar (17%). There was no statistically significant difference in the levels of dental fluorosis between children living in fluoridated areas who were fed formula as infants (31%) and those who were not (34%). Children living in fluoridated areas had statistically significantly lower mean caries experience in the primary dentition at age 8 or 9 years (DMFS 2.18) compared to those living in non-fluoridated areas (DMFS 3.95). There was no statistically significant difference in dental caries between children living in non-fluoridated areas who were fed formula as infants and children from the same area who were not fed formula. 27

28 Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD GOOD Use of infant formula in areas with water fluoridation was not associated with dental fluorosis when there was control for the effects of confounding factors. Strengths: Population based nested case control study Random sampling method used to select study subject. Examiners calibrated and blinded to fluoride status of children examined. A reference group of non-formula fed children was used to calculate unadjusted risk ratios. Controlled for potential confounding by age, sex, socioeconomic status and other fluoride sources. Limitations: Parental questionnaire on infant feeding practices was carried out when children were aged 8-13 years leading to risk of recall error. Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Other sources of fluoride were unevenly distributed. More toothpaste was used in fluoridated areas whilst more fluoride supplements were given in non-fluoridated areas. The study does not show an increase in dental fluorosis when combining formula milk with fluoridated water. 28

29 [4*] Date: September/ October 2011: Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Dental Health in the United Kingdom and Influencing variables Drugan CS, Downer MC Bundesgesundheitsblatt- Gesundheitsforshung- Gesundheitsschutz / Oral and Public Health Epidemiology To review four key topics pertaining to the oral health of the United Kingdom (UK): (1) provision of state-funded dentistry, (2) trends in oral health, (3) dental caries prevention, and (4) determinants of dental health. Methods: Data were abstracted, mainly from peerreviewed publications in the literature. Information was updated where appropriate. Results: Since the 1948 inception of the National Health Service (NHS) and its General Dental Service (GDS), the system of providing dentistry has evolved in response to changing fiscal and health circumstances. Since the 1970s, the oral health of the population, both children's dental decay experience and the decline adult tooth loss, has improved steadily and substantially. Approaches towards prevention are discussed and the dominant position of water fluoridation highlighted. The determinants of dental health are analysed. Conclusion: Dental caries experience of children in the UK and the rest of Europe is highly correlated with national wealth as are two other significant determinants: fluoride toothpaste and sugar consumption. The activity of dental professionals appears to have only a limited influence on levels of oral health. There is reason to believe that UK water fluoridation coverage may broaden. Study Location: Study Dates: Study Design: Study validity: UK N/A Commentary Low Key Points: The paper was a commentary on factors influencing oral health. There was a rapid decline in the rates of DMFT in 12 year olds in the UK in the 1980 s followed by a steady decline. DMFT in 5 year olds in the UK fell from 1.8 to 1.6 between 1983 and The North of England had higher rates of tooth decay than the South. Water fluoridation achieves the highest health benefits versus costs out of all oral public health interventions examined. This is due to other measures relying on co-operation and compliance along with close day to day management. The difference in severity of dental caries (mean DMFT) amongst children between fluoridated and non-fluoridated water areas increases (from 24-50%) with increased levels of deprivation. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the N/A GOOD 29

30 conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Comprehensive review examining national trends in oral health in the United Kingdom over a wide time frame. Limitations: A commentary Can the findings be generalised? National data used therefore provides an general overview Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Broadly supports water fluoridation both as a means to reduce the incidence of dental caries and socio economic differences in oral health. However, this is a commentary rather than a study. 30

31 [5*] Date: November 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Intelligence Quotients of year old school children in a high and low fluoride village in India Eswar P, Nagesh L, Devara CG Fluoride (3) Oral and Public Health Epidemiology The aim of this preliminary study was to compare the intelligence quotient (IQ) scores of year old school children living in a high fluoride (F) village with the IQ scores of a similar group of children in a low F village in the Davangere district, Karnataka, India. Sixty-five children from the one high school in the low F water village of Ajjihalli (F = 0.29 ppm) and 68 children from the one high school in the high F village of Holesirigere (F = 2.45 ppm) were selected by convenience sampling. Water F levels were estimated by the F ion selective electrode method. IQ scores were measured using Raven's Standard Progressive Matrices test. Chi-square and Z tests were used for statistical analysis of data. In the high F village of Holesirigere the mean IQ score of the 68 children was lower (86.3 +/- 12.8) than in the low F village of Ajjihalli, where the mean IQ score of 65 children was higher (88.8 +/- 15.3), but the difference was not statistically significant (p = 0.30) The number of children with IQ scores < 90 was 43/68 (63.2%) in high F Holesirigere and 31/65 (47.7%) in low F Ajjihalli, a difference that is nearly but not quite statistically significant (p = 0.06). The trend was toward lower IQ with high F water, even though these preliminary findings indicated that the F level in the drinking water was not significantly associated with IQ scores of year old children in the high and low F villages. Study Location: Study Dates: Type of Study: Validity of Study: Davangere District, Karnataka, India Not given Cohort Study Low Key Points: There was no statistically significant difference between the mean IQ in the village with high water fluoride concentration, compared to the village with low water fluoride concentration. There was no statistically significant difference between children with an IQ of less than 90 (below average) in the village with high water fluoride concentration (63.3%), compared to the village with low water fluoride concentration (47.7%). The authors stated that the explanation for differences in IQ could not be said to be solely associated with water fluoride: IQ, however, is known to be influenced by many factors including differences in biological susceptibility, environmental conditions, and measurement errors. Variables like nutrition, prenatal care, breast feeding, stimulating environment, parental IQ, endemic iodine deficiency, freedom from disease, physical trauma, good schooling, and maternal exposure to F during pregnancy play a large role in determining IQ development. F in drinking water is therefore just one among these several environmental factors affecting the IQ of children. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? FAIR FAIR 31

32 Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? NO as the conclusion is based on a non-statistically significant trend NO see above Strengths: Children accepted into the study were continuous residents of their village since birth Water samples were taken from public water supply Limitations: Confounding factors were not controlled for. Low validity study in an area with high water fluoride concentration Can the findings be generalised? Only to areas with naturally very high water fluoride concentrations Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE the differences in children s IQ between villages with high and low water fluoride concentration were not statistically significant, and therefore could have occurred by chance. In addition the study was conducted in an area where natural fluoride concentrations in water were well in excess of those used for NZ CWF. In addition, other factors, which may contribute to differences in levels of intellectual development, were not investigated. 32

33 [6*] Date: November 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Modelling the impact of process variables in community fluoridated milk schemes on a population of UK children Forster GRK, Downer MC, Tickle M British Dental Journal Oral and Public Health Epidemiology There is cause for concern about the effectiveness of fluoridated milk schemes as a standalone measure for the prevention of caries in children. While optimising some process variables looks promising, resources may be more efficiently spent on other fluoride interventions. Modelling would inform speculative power calculations for community-based trials of fluoridated milk. Background: Dental caries is a public health problem. Fluoridated milk (FM) schemes are used as a preventive measure. The impact of process variables in these schemes is not understood. Methods: Process variable data on the number of days of consumption, attendance, volume consumed, parental consent together with the proportion of children drinking FM at 7 and 11 years old were aggregated from eight schemes in the UK. The impact of process variables was modelled in an 'averaged' scheme (reduced in effectiveness by process variables) and compared with a notional 'ideal' one in which no process variables operate. Parental consent was analysed according to socio-economic groupings. Results: Proportion of days per year FM was consumed: Values for process variables were: attendance rate 0.94; proportion of milk consumed 0.91; proportion of children with parental consent at 5 years 0.65; proportion drinking FM t 7 and 11 years respectively 0.54 and No clear trends were observed for parental consent across socioeconomic groupings. Conclusion: Modelling suggests that due to the cumulative impact of process variables, there is cause for concern about the effectiveness of FM schemes as currently managed in the UK as a standalone public health measure for the prevention of caries. Study Location: Study Dates: Type of Study: Validity of Study: United Kingdom Not given Ecological study Low Key Points: Since 1993 fluoridated milk has been used as a prophylactic measure in 16 districts of the UK which has high rates of dental caries and no water fluoridation. Continuation of consent (therefore participation in the fluoridated milk scheme) was linked to the school environment. Modelling suggests that due to the cumulative impact of process variables, there is cause for concern about the effectiveness of FM schemes as currently managed in the UK as a standalone public health measure for the prevention of caries. No trends were observed between consent in the fluoridated milk scheme and socio economic status. Consent was lowest in the socioeconomic Quintile 1 (most deprived) followed by Quintile 5 (least deprived). Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is 33

34 appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR AVERAGE Strengths: Provides a method for monitoring the effectiveness of this type of intervention Limitations: Does not allow for confounding by: other sources of fluoride, consumption refusal and failure of milk deliveries. Fluoride content in milk not estimated therefore increased intake could not be determined. Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 34

35 [7] Date: September/ October 2011: Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Study Location: Study Dates: Study Type: Validity of Study: Drinking water quality and fluoride concentration Frazāo P, Peres MA, Cury JA Rev. Saūde Pūblica (5) 1-9 Oral and Public Health Epidemiology This paper aimed to analyse the fluoride concentration in drinking water, taking into account the balance between the benefits and risks to health, in order to produce scientific backing for the updating of the Brazilian legislation. Systematic reviews studies, official documents and meteorological data were examined. The temperatures in Brazilian state capitals indicate that fluoride levels should be between 0.6 and 0.9 mg F/l in order to prevent dental caries. Natural fluoride concentration of 1.5 mg F/l is tolerated for consumption in Brazil if there is no technology with an acceptable cost-benefit ratio for adjusting/removing the excess. Daily intake of water with a fluoride concentration > 0.9 mg F/l presents a risk to the dentition among children under the age of eight years, and consumers should be explicitly informed of this risk. In view of the expansion of the Brazilian water fluoridation program to regions with a typically tropical climate, Ordinance 635/75 relating to fluoride added to the public water supply should be revised. Brazil Not given Review/Ecological study Low Key Points: It was suggested that in Brazil, safe water fluoride concentrations should be at the lower end of the WHO scale ( mg/l). In the Brazilian market, 10.6% of 104 commercial brands of bottled water were found to have water fluoride concentrations of >0.7mg/l. It was suggested that bottled water might also contribute to dental fluorosis in Brazil. An international review of the literature did not support an association between water fluoridation and cancer or bone fracture. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? N/A Strengths: Comprehensive review of literature and National data Covered a wide range of influences on dental health including: water fluoride level, 35

36 water consumption and climatic conditions. Limitations: The report was based on secondary data or ecological (collective) data. Can the findings be generalised?, but only to similar regions The period of exposure and risk of dental caries/ risk of dental fluorosis were not investigated. Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO Fluoride concentration in some bottled waters in New Zealand may be below optimal fluoride concentration recommended by the Ministry of Health to prevent tooth decay. The Australasian Bottled Water Institute (ABWI) states that: The regulations in Australia and New Zealand permit the voluntary addition of Fluoride to still, packaged water at a range of 0.6-1mg/L (total of added and naturally occurring fluoride) which reflects that of the municipal water supply in Australia and New Zealand. As a legal requirement, any bottled water sold in Australia and New Zealand which has added Fluoride must state clearly on the label that the product contains added fluoride. The addition of Fluoride to bottled water was made legal in July Prior to this date, bottled water was criticised for not containing fluoride. 36

37 [8*] Date: November 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Dental fluorosis- a case study from Nawa tehsil in Nagaur district, Rajasthan (India) Gautam R, Bhardwaj N, Saint Y Environmentalist Oral and Public Health Epidemiology A study was carried out in Nawa tehsil of Nagaur district to assess the prevalence of dental fluorosis and its crippling effect due to ingestion and prolonged exposure of fluoride over a long period of time. During the survey of the study area, high concentration of fluoride ( ppm) has been recorded. The presence of fluoride in quantities in excess of limits is a serious matter of concern from a public health point of view. Due to higher fluoride level in groundwater, several cases of dental fluorosis have appeared at alarming rate in the study area. The children's teeth are damaged and are characterized by black and brown stains as well as cracking and pitting of the teeth have been observed. In the study area, % population suffered from dental fluorosis, and it was more prevalent in men (94. 90%) than in women (90. 00%). Dental fluorosis was also examined according to different grades. Out of the total 72 afflicted, in the 4-16-year age group, % were suffering from Grade I, Grade II was more prevalent in % of the year age group and similarly Grade II was more prevalent in % of the year age group. In the age group of above 40 years, grade III and grade IV were more prevalent. Thus, in the higher age group, the prevalence and severity of fluorosis is almost certainly due to longer exposure to fluoride. The major risk factor consistently identified for dental fluorosis was the consumption of fluoridated drinks and fluoride supplements. Ingestion of calcium, vitamin D and vitamin C is effective in protection from fluoride toxicity to certain extent. Study Location: Study Dates: Type of Study: Validity of Study: Nagaur District, Rajasthan, India Not given Prevalence study Low Key Points: Water fluoride content in the study area was ppm. Altogether 93.1% of the study population displayed some form of fluorosis, with the rate of fluorosis increasing with age which was suggested to be related to exposure. Boys (87.5%) had a higher rate of fluorosis than girls (66.7%) and the authors suggested this could be linked to gender related water consumption. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR FAIR 37

38 Strengths: Detailed questionnaire based study Limitations: Low sample size, especially when stratified by confounding factors such as age Can the findings be generalised? NO specific to the climatic and geological conditions of the area which has high natural fluoride concentrations Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE low validity study in a high fluoride area 38

39 [9*] Date: November 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Assessing and managing fluorosis in children and adults in rural Madhya Pradesh, India Godfrey S, Pawan L, Tapas C, Satish W, Aditya S, Bartram J Journal of Water, Sanitation and Hygiene for Development Oral and Public Health Epidemiology This paper presents the application of quantitative chemical risk assessment for assessing and managing fluorosis in 19 schools and 6 villages in Madhya Pradesh, India. A longitudinal study was undertaken with a baseline survey in 2005 and an end line in Household surveys, water quality and food analysis were undertaken to measure the impact of an Integrated Fluorosis Mitigation programme that included water and nutritional interventions. The baseline survey indicated a maximum fluoride content of 7.8 mg/l in food and 3.7 mg/l in water, equating to a maximum fluoride uptake of 4.8 and 3.7 mg/l in food and water respectively. Mean (actual) daily intake of fluoride for all exposure routes was 0.4 mg/kg of combined adult and child body weight. Intake of fluoride through food was more than 40% of total intake. Calculated guideline values for age groups <18 years and >18 years were 1.7 and 1.9 mg/l respectively. Using WHO methodology, the Guideline Value would be 1.7 mg/l. Fluoride dilution was implemented to reduce the fluoride content to below this level. The end-line survey indicated reduction in the prevalence of grade 1 fluorosis of 86%, of grade 2 of 77%, of grade 4 of 60% in all children examined. Study Location: Study Dates: Type of Study: Validity of Study: Madhya Pradesh, India Longitudinal Risk Assessment and Mitigation Study High Key Points: High levels of fluoride in water and food led to high prevalence of dental fluorosis (49.9%) and evidence of skeletal fluorosis (11.8%) Mitigation measures such as diluting groundwater with rainwater led to a reduction in the prevalence of fluorosis. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD GOOD Strengths: Very comprehensive, scientifically rigorous study Limitations: Small area study Not relevant to the New Zealand context as the study is concerned with reducing naturally very high water fluoride concentrations to reduce fluorosis prevalence in an area where it is endemic. 39

40 Can the findings be generalised? NO specific to the climatic and geological conditions of the area Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 40

41 [10*] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Amoxicillin use during early childhood and fluorosis of later developing tooth zones Hong L, Levy SM, Warren JJ, Broffitt B Journal of Public Health Dentistry Oral and Public Health Epidemiology Amoxicillin use has been reported to be associated with developmental defects on enamel surfaces. This analysis assessed the association between amoxicillin use and fluorosis on lateerupting permanent teeth. Methods: As part of the Iowa Fluoride Study, subjects were followed from birth to 32 months with questionnaires every 3-4 months to gather information on fluoride intake and amoxicillin use (n = 357 subjects for this analysis). Permanent tooth fluorosis on late-erupting zones was assessed by three trained dentists using the fluorosis risk index (FRI) at approximately age 13. A case was defined as fluorosis if a subject had at least two FRI classification II zone scores of 2 or 3. Chi-square tests and logistic regression were used, and relative risks (RRs) and odds ratios (ORs) were calculated. Results: There were 113 cases and 244 controls. In bivariate analyses, amoxicillin use from 20 to 24 months significantly increased the risk of fluorosis on FRI classification II zones [44.2 percent versus 30.4 percent, [RR = 1.45, 95 percent confidence interval (CI) ], but other individual time periods did not. Multivariable logistic regression confirmed the increased risk of fluorosis for amoxicillin use from 20 to 24 months (OR = 2.92, 95 percent CI = ), after controlling for otitis media, breast-feeding, and fluoride intake. Conclusions: Amoxicillin use during early childhood could be a risk factor in the etiology of fluorosis on late-erupting permanent tooth zones, but further research is needed. Study Location: Study Dates: Study Type: Study Validity: Iowa, USA Case-control study Medium Key Points: Amoxicillin use at months had a statistically significant association with fluorosis in late erupting permanent teeth. A dose response relationship was also demonstrated in this age group. High level and middle level fluoride intake at months and months also had a statistically significant association with fluorosis Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR 41

42 Strengths: A wide range of influencing factors were controlled for: sex, family income, mother s education, use of other antibiotics, low birthweight, otitis media, developmental disorders, breastfeeding and estimated yearly fluoride intake. Limitations: A convenience sample was used resulting in most children coming from high socioeconomic backgrounds Questionnaires on the use, frequency and duration of amoxicillin were selfadministered by parents and not verified through records. No adjustment was made for testing at times of multiple exposures. Exact figures for categorising fluoride intake into high, medium or low levels were not stated in the text. It is only stated that they were based on milligrams per kilogram bodyweight per day, estimated from food and beverage consumption. Can the findings be generalised? to similar populations: white, medium to high socioeconomic status families Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE the paper has nothing to do with CWF 42

43 [11*] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Site specific toxicological risk from fluoride exposure through ingestion of vegetables and cereal crops in Unnao district, Uttar Pradesh, India Jha SK, Nayak AK, Sharma YK Ecotoxicology and Environmental Safety Oral and Public Health Epidemiology A study was carried out to assess toxicological risk from the fluoride (F) exposure due to ingestion of vegetables and cereal crops such as rice and wheat grown in potentially fluoridated area (brick kiln and sodic areas), of different age groups in Unnao district, Uttar Pradesh, India. Fluoride contents in vegetables and cereal were found to be in the order brick kiln sites > sodic sites > normal sites. Among vegetables maximum F concentration was found in spinach and mint, whereas in cereal crops, wheat accumulated more F than rice. The exposure dose of F was determined using estimated daily intake (EDI) and bio-concentration factor (BCF) of F. The children of age group 3-14 years in the potentially fluoridated area were found to be at the risk of fluorosis. The mean BCF value of F was the highest in mint (36.6 mg/kg(dwt) plant/mg/kg(dwt) soil), followed by spinach (33.99 mg/kg(dwt) plant.mg/kg(dwt) soil). Study Location: Study Dates: Study Type: Study Validity: Unnao District, Uttar Pradesh, India Ecological Study Medium Key Points: The study measured the fluoride content in a range of commonly grown vegetable and cereal crops and used a Household Nutritional Survey to calculate the average intake of each. Fluoride in solution rather than fluoride content of the soil is correlated to uptake by plants. Fluoride concentrations were related to soil structure, with low-clay soils yielding higher soluble fluoride and therefore more fluoride in food crops tested. Fluoride accumulation was highest in spinach and mint. It is suggested that this might be due to airborne fluoride in pollution being absorbed by the leaf stoma. In cereal crops accumulation was greater in wheat than in rice. Estimated daily intake (EDI) of fluoride was higher in industrial areas. Brick kilns were associated with highest EDI, followed by sodic soils, followed by normal soils. Cereal crops were responsible for a greater part of EDI than vegetables. In brick kiln and sodic soils, based on EDI of the food crops tested, children aged 3-14 years exceeded the upper limit set for fluoride intake by the Institute of Medicine (IOM in the USA). No other age group (15-18 year olds and those aged years) exceeded this limit. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? FAIR 43

44 Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Primary data collection method for food crop fluoride concentration Comprehensive study examining the impact of multiple variables: age, soil structure, soluble fluoride levels, type of crop, land use (related to industry). Limitations: EDI was calculated using secondary data. Drinking and cooking water consumption was not taken into account for EDI EDI represents ingestion of fluoride but not the rate of absorption by the body Can the findings be generalised? NO they are related to food grown under specific environmental conditions in an area where there was a high risk of fluorosis Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO the study was carried out to examine fluoride consumption from a range of food crops (serials and vegetables). Risk from fluorosis was linked to from brick kilns and sodic areas. NONE 44

45 [12] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Dental Caries in Rural Alaska Native Children Klejka J, Swanzy M, Whistler B, Jones C, Bruce MG, Hennessy TW, Bruden D, Rolin S, Beltran- Aguilar E, Byrd KK., Husain F Morbidity and Mortality Weekly Oral and Public Health Epidemiology Summary of Study: Abstract: Study Location: Study Dates: Study Type: Study Validity: None provided Alaska, USA April 2008 Cross-sectional study Medium Key Points: This study investigated dental caries and associated risk factors of dental caries in five remote Alaskan villages, two with fluoridated water and three without. Native Alaskan children had greater rate of dmft/dmft compared to same aged children in the USA. Children from villages without water fluoridation had 57-91% one or more missing, filled or decayed tooth compared to 31-91% of those with fluoridated water. The adjusted odds ratio (AOR) for increased dental caries due to nonfluoridated water was 3.5 for primary dentition and 1.7 for permanent dentition. Level of soda pop consumption was positive associated with number of dmft/ DMFT. Children who drank one bottle of soda pop per day had an AOR of 1.1 for caries in primary dentition and 1.3 for caries in permanent dentition. The AOR increased to 1.5 and 2.0 respectively when daily consumption of soda pop increased to three bottles. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD Strengths: The study used primary data linking all information to individual children (ie, questionnaire and dental examination) The study controlled for potential confounding effects of age, sex, oral health 45

46 behaviour, e.g. tooth brushing and access to dental care Limitations: Can the findings be generalised? Limited ability to generalise as this was a native population in a rural area with lack of access to dental care good last point Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Yes - emphasises the advantage of water fluoridation amongst indigenous populations in remote rural communities Supports water fluoridation in remote indigenous communities with limited access to dental care. 46

47 [13*] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Study Location: Study Dates: Study Type: Study Validity: Assessment of periodontal status among dental fluorosis subjects using community periodontal index of treatment needs Kumar PR, John J Indian Journal of Dental Research (2) Oral and Public Health Epidemiology To determine the periodontal status and treatment needs among dental fluorosis subjects residing in Ennore, Chennai, using Community Periodontal Index of Treatment Needs (CPITN). Materials and Methods: All the subjects with dental fluorosis above 15 years of age, permanent residents of Ennore, were included in the study. Subjects with known systemic diseases and subjects with other intrinsic dental stains were excluded from the study. Periodontal status was estimated using CPITN and Dental fluorosis was recorded using Dean's Dental Fluorosis Index. Results: The total number of study subjects was 1075, of which 489 were males and 586 were females. Males were predominantly affected with periodontal disease than females. This was found to be statistically significant (P=0.000). The association between Degree of Fluorosis and Periodontal Status is statistically significant (P=0.000). There was statistically significant difference in mean number of sextants between the degree of fluorosis in each of the periodontal status (P=0.000). Conclusion: The finding that the lower prevalence of shallow pockets in the study area, where the fluoride level in the drinking water ranges from 1.83 to 2.01ppm, indicates that the use of fluoride in water is beneficial to the periodontal tissues. Ennore, Chennai, India Not given Cross sectional study Low Key Points: The study population consisted of those over 15 years of age who were permanent residents of Ennore and who suffered from dental fluorosis. Those with a systemic disease or other (non-fluorosis) dental staining were excluded from the study. Males were predominantly affected with periodontal disease than females. The association between degree of fluorosis and periodontal status is statistically significant. The authors suggested that finding that the lower prevalence of shallow pockets in the study area, where the fluoride level in the drinking water ranges from 1.83 to 2.01 ppm, indicates that the use of fluoride in water is beneficial to the periodontal tissues. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid NO FAIR UNCLEAR 47

48 conclusions with respect to the initial hypothesis/aim? UNCLEAR AND DID NOT DIRECTLY ADDRESS THE AIM Strengths: An individual cross sectional study using a random sampling method Limitations: No comparative assessment was made with an area with low/ negligible water fluoride levels Can the findings be generalised? NO Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Direct comparison with other studies could not be made due to differences in population and methodologies NO Water fluoride content in the study area is much higher than that found in New Zealand NONE: Low validity and in an area with naturally high water fluoride levels above those used for NZ CWF. 48

49 [14] Date: December 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Fluoride in drinking water and osteosarcoma incidence rates in the continental United States among children and adolescents Levy M, LeClerc B-S Cancer Epidemiology Not given Oral and Public Health Epidemiology Introduction: It has been suggested that fluoride in drinking water may increase the risk of osteosarcoma in children and adolescents, although the evidence is inconclusive. We investigated the association between CWF and osteosarcoma in childhood and adolescence in the continental U.S. Methods: We used the cumulative osteosarcoma incidence rate data from the CDC Wonder database for , categorized by age group, sex and states. States were categorized as low ( 30%) or high ( 85%) according to the percentage of the population receiving CWF between 1992 and Confidence intervals for the incidence rates were calculated using the Gamma distribution and the incidence rates were compared between groups using Poisson regression models. Results: We found no sex-specific statistical differences in the national incidence rates in the younger groups (5-9, 10-14), although males were at higher risk to osteosarcoma than females in the same age group (p<0.001). Sex and age group specific incidence rates were similar in both CWF state categories. The higher incidence rate among year old males vs. females was not associated with the state fluoridation status. We also compared sex and age specific osteosarcoma incidence rates cumulated from 1973 to 2007 from the SEER 9 Cancer Registries for single age groups from 5 to 19. There were no statistical differences between sexes for 5-14 year old children although incidence rates for single age groups for year old males were significantly higher than for females. Conclusion: Our ecological analysis suggests that the water fluoridation status in the continental U.S. has no influence on osteosarcoma incidence rates during childhood and adolescence. Study type: Location of Study: Time of Study: Validity of Study: Ecological Study USA Medium Key Points: No statistically significant difference was found between rates of osteosarcoma in states with high water fluoridation (over 85% of the population have access to fluoridated water) and those with low water fluoridation (less than 30% of population have access to fluoridated water). Rates of osteosarcoma were not statistically significantly different between males and females in age groups 5-9 and years. In the age group there was a statistically significant increased rate of osteosarcoma in males compared to females. The authors concluded that their ecological analysis suggests that the water fluoridation status in the continental USA has no influence on osteosarcoma incidence rates during childhood and adolescence. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? AVERAGE 49

50 Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: The databases used are very broad, therefore a large dataset was available for the study Two separate databases (SEERS and CDC Wonder) were used, both yielded the same results Limitations: The ecological design therefore means that individual relationship between water fluoride exposure and risk of osteosarcoma was not investigated. Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Does not support a link between community water fluoridation and osteosarcoma in children and adolescents at the state level. The authors stated that: Our ecological analysis suggests that the water fluoridation status in the continental U.S. has no influence on osteosarcoma incidence rates during childhood and adolescence. 50

51 [15*] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Study type: Location of Study: Time of Study: Validity of Study: Use of Professionally Administered Topical Fluorides in Asia Lo ECM, Tenuta LMA, Fox CH Advances in Dental Research :11 Not given Oral and Public Health Epidemiology Professionally applied topical fluoride varnish, gel, and solution have been shown to be effective in preventing and in arresting dental caries. Their use in different countries in Asia varies greatly and may not correlate with the dental caries situation of the populations in the countries. In the higher-income countries, use of fluoride varnish and gel is common among dental professionals. In contrast, the use of professionally administered topical fluorides is not common in the lower-income countries. Fluoride varnish, being easy to apply and safe, has been the preferred agent for the prevention of early childhood caries, which is prevalent in many developing countries in Asia. The relatively high cost of professionally administered fluoride agents and the shortage of a dental workforce, especially in lower income countries, have hampered the widespread adoption of these effective caries prevention methods in the private and public dental services. Government health policies should be pursued to lower the cost of treatment, either through incentives for local production and/or elimination of taxes and tariffs on imported fluoride products. N/A Discussion Paper Phang-Nga, Thailand 2011 N/A discussion paper Key Points: Many Asian countries offer topical fluoride treatments for those with high caries risks, either through public or private oral health care. This is a relatively easy method of caries prevention at community level. Challenges include lack of trained workforce and infrastructure, particularly in rural areas Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Limitations: N/A Discussion paper N/A N/A N/A N/A N/A N/A Can the findings be generalised? LIMITED due to focus on low to middle income countries Are the findings applicable to water fluoridation in New NO 51

52 Zealand? Implications for the Ministry of Health water fluoridation policy: NONE 52

53 [16*] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Study type: Location of Study: Time of Study: Study Validity: Fluoride content and distribution pattern in groundwater of eastern Yunnan and western Guizhou, China Luo K, Lui Y, Li H Environ Geochem Health Oral and Public Health Epidemiology For study, the fluoride (F) content and distribution pattern in groundwater of eastern Yunnan and western Guizhou fluorosis area in south-western China, the F content of 93 water samples [groundwater (fissure water, cool spring, and hot springs), rivers water] and 60 rock samples were measured. The result shows the F content of the fissure water and cold spring water is mg/L, and river water is mg/L. The F content of hot spring water is mg/L. The drinking water supplied for local resident is mainly from fissure water, cool spring, and river water. And the F content in all of them is much lower than the Chinese National Standard (1.0mg/L), which is the safe intake of F in drinking water. The infected people in eastern Yunnan and western Guizhou fluorosis area have very little F intake from the drinking water. The hot spring water in fluorosis area of eastern Yunnan and western Guizhou, southwest China has high F content, which is not suitable for drinking. Prevalence Study Eastern Yunnan and western Guizhou, China Not stated Medium Key Points: The study aimed to identify possible fluoride sources causing the fluorosis which is in the study region. Possible sources of fluoride exposure include: indoor coal combustion, drinking water fluoride concentration and consumption of brick tea. Drinking water in endemic region was well below the maximum water fluoride concentration of 1.0mg/L which is standard in China. Fluoride absorption from the bedrock increased with increased water temperature Fluorosis infected people from Yunnan and Guizhou has very low fluoride intake from drinking water. It was suggested that the source of fluorosis was the use of coal burning ovens which are used to dry out corn, the stable diet in the area. Testing identified that the fluoride content in the corn increased by times after 10 days drying out in a coal fired oven. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD 53

54 Strengths: Limitations: Secondary data used to link fluorosis to oven dried corn and capsicum Can the findings be generalised? NO Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NONE NONE 54

55 [17*] Date: December 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Fluoride Concentration of Drinking Water in Babil, Iraq Matloob MH Journal of Applied Sciences (18) Oral and Public Health Epidemiology The role of fluoride in reducing the risk of dental caries is well documented and is the basis for current intake recommendations. The aim of this study was to evaluate the fluoride content of tap and bottled water currently consumed in Babil-Iraq and to determine whether fluoride intakes by Iraqi consumers fell within the recommended ranges. Fluoride concentrations of 50 samples of tap water (originated from the Euphrates River) and forty popular brands of bottled water currently sold in Babil-Iraq were determined using an Ionselective electrode. The mean fluoride content of tap and bottled water were 0.184±0.041 and 0.073±0.066mg L -1, respectively. The average volume of water consumed by Iraqi adults daily was estimated to be 800±240mL in winter to 2000±650mL in summer. Based on these data the average daily intake of fluoride by Iraqi consumer from tap and bottled water were 0.147±0.055 to 0.368±0.145mg and 0.058±0.056 to 0.146±0.140mg, respectively. These levels revealed that whether tap or bottled water are used as the primary source of drinking water, then Iraqi consumers are at a higher risk of tooth decay. Water fluoridation is recommended as a relevant public health measure to increase the resistance to dental caries. Study type: Location of Study: Time of Study: Study Validity: Water sampling Babil Province, Iraq June May2011 Medium Key Points: The fluoride concentration of Babil s tap water, ranged from to 0.260mg L -.These levels are considered by WHO to be insufficient to prevent caries The mean fluoride content of 28 bottled waters manufactured in Iraq was 0.073mg L -1 (range mg L -1 ). Daily fluoride intake in Babil was calculated at ±0.055 to ±0.145mg for tap water and ± mg to ±0.140 mg for bottled water. Fluoride levels in tap water were considered insufficient to prevent caries and the levels in bottled water were even less. Therefore, in this region, neither tap water nor bottled water independently was sufficient to prevent caries. Water fluoridation is recommended as a relevant public health measure to increase the resistance to dental caries. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid FAIR 55

56 conclusions with respect to the initial hypothesis/aim? Strengths: Quantitative study of water fluoride content Consumption rates calculated using primary data Limitations: Convenience sample used for calculating daily water consumption, using a narrow population group (students aged years) There was no relationship considered between fluoride and caries/other oral health effects. The authors only considered the levels of fluoride from tap and bottled water Can the findings be generalised? PARTIALLY Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Consumer preference for bottled water may affect water as a supplementary source of fluoride. It may be appropriate to investigate water consumption habits (bottled/ tap etc.) as a means to calculate water fluoride concentration required to reach optimal daily fluoride intake. It may be appropriate to consider labelling concentration of fluoride on bottled waterthis is currently only required if fluoride is added to water in Australia and New Zealand. 56

57 [18*] Date: September /October 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Relationship of caries and fluorosis in adolescents from high and low fluoride areas in Iran Meyer-Lueckel H, Bitter K, Khorrami G, Kielbassa AM, Paris S Community Dental Health Oral and Public Health Epidemiology Objective: The main aim of the study was to investigate the association between water fluoride concentration and caries as well as fluorosis occurrence in adolescents in Iran. As a secondary aim we studied the relationship between caries and fluorosis occurrence. Basic research design: We examined year-olds (n=373) in Orumiyeh [0.3 mgf-/l, low-fluoride (LF)] and Pol Dasht [3.2 mgf-/l, high-fluoride (HF)] for caries-status [D3-Level, Pitts & Fyffe (DMFS)] and fluorosis prevalence [Thylstrup & Fejerskov index (TF)]. Children completed questionnaires about several socio-demographic and oral health related factors of the previous years. To adjust for confounding, we used log risk regression and estimated relative risks (RR) and 95% confidence intervals (CI). Results: For year-olds mean DMFS were 1.9 (sd 2.5) and 1.1 (2.2) in the LF and the HF-areas, respectively. Prevalence of aesthetically relevant fluorosis (TF>2) was 1% (LF) and 87% (HF). Water fluoride concentration (adjusted for age and SES) was inversely associated with caries-status [RR: 0.7, (CI )]. RR for fluorosis was 17 (CI 8-33). In HF-area, caries scores were significantly higher for children with TF 5 on upper central incisors compared with TF 4 (p<0.05 Mann-Whitney test). Conclusions: Caries prevalence in the examined areas in Iran is quite low. Above optimal water fluoride concentration seems to be effective in reducing caries experience, but increases the occurrence of fluorosis. Severe fluorosis seems to be associated with higher caries occurrence in a high-fluoride area. Study Location: Study Dates: Study Type: Study validity: West Azerbaijan, Iran April 2004 Cohort Study Medium Key Points: Water fluoride concentration (adjusted for age and SES) was inversely associated with caries-status It was concluded that above optimal fluoride concentrations (in the high fluoride area) led to a decrease in caries in adolescents (life-long residents only) but also an increase in severity of fluorosis suffered. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR Strengths: Intra individual examiner reliability was tested and found to be 0.87 denoting good agreement 57

58 Both fluorosis and caries experience was divided into life-long and non-life-long residents in for the high fluoride area. The response rate was very good. More than 95% of the targeted study population took part. Limitations: A convenience sample was used which could result in selection bias. Whilst confounding for socioeconomic status was controlled for, use of father s occupation to classify status may have led to some misclassification. Due to a small/ inadequate sample size, severity of fluorosis could not be analysed. Can the findings be generalised? NO - the high fluoride levels are greater than those found in New Zealand Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO see above NONE see above 58

59 [19*] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Study type: Location of Study: Time of Study: Study Validity: Prevalence and severity of dental fluorosis in relation to fluoride in ground water in the villages of Birbhum District, West Bengal, India Mondal NK, Pal KC, Kabi S Environmentalist 2012 Not given (online publication) Not given (online publication) Oral and Public Health Epidemiology In relation to fluoride in ground water, dental fluorosis is studied in seven villages, viz., Nasipur, Vabanandapur, and Deshnabagram under Nalhati I block and Kamdebpur, Chalk Atla, Nowapara, and Junitpur under Rampurhat II block, of Birbhum district, West Bengal, India. Water samples (N = 70) were collected from the tube wells of the mentioned villages in the months of December 2010 to February 2011 and analysed for fluoride and other water parameters. The study result revealed that the fluoride levels of almost all the water samples (95.7%) were higher than 1.5 mg/l, with mean values of 3.15 and 3.83 mg/l in Nalhati I block and Rampurhat II block, respectively. Dental fluorosis of 490 respondents was visually determined by a competent dentist using Dean's index (DI) and the tooth surface index of fluorosis (TSIF). According to the DI, the percentage of severely affected respondents was lowest in Chalk Atla (0%) and highest in Deshnabagram (50%). The percentage of severely affected respondents was lowest in Kamdebpur and Chalk Atla (0%) and highest in Nowapara (20%) according to the TSIF score. The age group years showed the highest percentage of severe DI (40.8%) and the age group years showed the highest percentage of severe TSIF (22.51%) compared to the other age groups in the study. The positive relationship between the fluoride level in water and the severity of dental fluorosis has been proved statistically. The high mean score of dental fluorosis indicates that dental fluorosis is endemic throughout the study area. Prevalence Study Birbhum District, West Bengal, India December 2012 to February 2011 Medium Key Points: Fluoride intake was calculated to be much higher in the study area (range >3.15mg/day to >4.21mg/ day in areas were >90% water samples had a fluoride concentration of >1.5mg/L), than those reported in a temperate climate (0.6mg/adult/day in areas without water fluoridation to 2.0mg/adult/day) in areas with water fluoridation The authors concluded: the inhabitants of these two blocks are in endemic fluoride pollution. The highest levels of fluorosis prevalence were found in the village with the highest water fluoride concentration (5.6mg/L) Higher rates of fluorosis were found in males (who were typically lifelong residents of the villages) compared to females (some of whom arrived in the villages on marriage). Prevalence of dental fluorosis varied widely between villages with similar water fluoride concentrations. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is 59

60 appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR Strengths: Exposure history traceable for individual residents Single examiner (dental hygienist) Limitations: It was not stated how were participants selected Only visual examination was carried out There was no examination of: dental caries, skeletal fluorosis or gastrointestinal illness was attempted, although these were mentioned as being linked to water fluoride concentration in the conclusion. No control for the effects of possible confounders. Can the findings be generalised? NO water fluoride concentrations above those used in NZ CWF Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO see above, also low mobility of population and differences in public dental health services provided. None 60

61 [20*] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Study type: Location of Study: Time of Study: Study validity: Studies on Dental Fluorosis in Low Fluoride Areas in the Southern Most Parts of India Murugan A, Subramanian A Australian Journal of Basic and Applied Science (11) Oral and Public Health Dental fluorosis, a global menace, especially in tropics, sub-tropics as well as temperate regions, is caused by water fluoride and other fluoride sources. As an endemic disease, dental fluorosis (df) has been reported from several countries including India. The present study tries to focus this human menace in low fluoride areas in Kanyakumari District, Tamil Nadu, India. The incidence of df is well documented in low fluoride areas, and a non-linear relationship is observed between the percentage prevalence of df and the drinking water fluoride concentrations. A high prevalence of df (32.56%) in low fluoride area (0.68 mg/l) and a low prevalence (12.51%) of df in high fluoride area (1.76 mg/l) is very well discussed. The study also explains the age and sex specific incidence of df. In males it is 21.42% and in females 19.98%. The inhibitory role of fluoride on various blood components is very clear in df cases. 'B' and 'O' blood group individuals are found more vulnerable to water fluoride intoxication than 'A' and 'AB' blood group people. Prevalence study Kanyakumuri District, Tamil Nadu, India Medium Key Points: The overall prevalence of dental fluorosis was 17.1% and was slightly higher in males (17.6%) than in females (16.7%). Children (aged 8-14 years) had higher rates of dental fluorosis (22.2%) compared to adults (11.8%) Water fluoride concentration in the study area ranged from 1.76 (± 0.085)mg/L to 0.67(± 0.047)mg/L (note: the abstract cites a different value for the low fluoride level = 0.68). Prevalence of dental fluorosis is positively correlated with water fluoride concentration Severity of fluorosis was not directly linked to water fluoride concentration and no dose response relationship is shown. The authors suggested there were differences in individual susceptibility to dental fluorosis one factor identified as a possible influence was blood type. O and B blood groups were found to have a higher prevalence of dental fluorosis than A and AB blood groups. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the FAIR 61

62 initial hypothesis/aim? Strengths: Quantitative methods used for water fluoride and blood sampling. Water samples taken over a year to allow for the influence of variations in climate Long term study (3 years) Limitations: Details of the study population not stated (including size, age, gender etc.) Sampling method not stated The populations history of fluoride exposure not stated Can the findings be generalised? NO this study was conducted in an area with endemic fluorosis Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO see above NONE see above 62

63 [21] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Fluoride Intake of Japanese Infants from Infant Milk Formula Nohno K, Zohoori FV, Maguire A Caries Research Oral and Public Health Epidemiology This study aimed to measure the fluoride (F) content of all infant milk formulas (IMF) available for purchase in Japan and estimate the F exposure of infants whose primary source of nutrition is IMF when reconstituted with different F concentrations of water. Twenty-two commercially available IMFs were purchased from 6 manufacturers in Japan. These IMFs included 21 milk-based products and 1 soy-based product. Each IMF was reconstituted using distilled water and 0.13µgF/ml fluoridated water according to the manufacturers' instructions. The F concentrations in each sample were measured using the hexamethyldisiloxane diffusion technique and an F ion-selective electrode. The mean F concentration of all products was 0.41 (range )µg/g. There were no statistically significant differences among mean F concentrations of newborn milks, follow-on milks and other milks or among manufacturers. The mean F concentration of all products, when reconstituted with distilled water and 0.13 µg F/ml water, was 0.09 and 0.18µg/ml, respectively. The mean F intake from IMF ranged from to 0.134mg/day with distilled water and from to 0.258mg/day with 0.13µg/ml fluoridated water, respectively. These results suggested that F intake of infants from IMFs depended on the F concentration of added water, and therefore the risk of dental fluorosis for most Japanese infants would be small since most Japanese municipal water supplies are low in F. However, there was a possibility to exceed the tolerable upper intake level, even under the limit of the law, especially for infants within the first 5 months of life. Study Location: Study Dates: Study Type: Study validity: Japan Not given Sampling of infant milk formulas and water Medium Key Points: The study assumed that infant milk formula (IMF) was the only infant food source. Measures of fluoride ingested (from IMF) were calculated using milligrams per kilogram body weight. Mean fluoride concentration in all IMF was 0.41 (range )µg/g. There was no statistically significant difference in fluoride content between newborn and follow on (6 months+) formula. There was no statistically significant difference in fluoride contents between milk manufacturers. Fluoride contents in all milks (including soy milk) were similar except in one formula where well water was used in its manufacture leading to higher fluoride content. The results of this study confirmed that the F intake of infants from IMF depends upon the F concentration of added water as shown in previous studies Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? 63

64 Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD Strengths: Laboratory controlled testing Limitations: Did not test level of absorption. Can the findings be generalised? 3 samples of each formula tested from 3 different batches to ensure consistency of formula. Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: : These results suggested that fluoride intake of infants from infant milk formula is dependent on the fluoride concentration of added water. However, the authors state: The resultant risk of dental fluorosis for most Japanese infants would be small since the F concentration of municipal water supplies provided in Japan is low. : The study provides advice on baby formula use in fluoridated/ non fluoridated water areas to ensure baby formula fluoride content is kept a range which minimises the risk of dental fluorosis. 64

65 [22*] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: The fluoride content of selected brewed and microwave-brewed black teas in the United States Pehrsson PR, Patterson KY, Perry CR Journal of Food Consumption and Analysis Oral and Public Health Epidemiology Fluoride (F) intake is recognized to be important for dental health. Tea leaves are known F accumulators and brewed tea as well as the water used for brewing may contribute significantly to individual intake. The USDA's Nutrient Data Laboratory determined the F content of brewed and microwaved teas using geographically matched tap water samples. Two brands of top-selling regular and one of decaffeinated teabags were purchased in 36 locations and brewed either by steeping in boiled water or with microwave heating followed by steeping. The mean F content for caffeinated regular brewed tea was 373 ± 49μg/100 g (n= 63) and for decaffeinated tea was 270 ± 46 μg/100 g (n= 34). The overall mean for F in microwaved regular tea was lower than regular brew (364 ± 40μg/100 g vs 322 ± 30μg/100 g (n= 36)). In all cases, prepared tea using water from the Midwest had the highest F-values. The mean F content of the brewed teas was 3-4 times higher than the national mean of the tap water, analysed separately (71±33μg/100 g). These data are the first nationally representative F-values for brewed teas, and will provide valuable information to the dental and medical research communities in assessment of fluoride intake and impact on dental health. Study Location: Study Dates: Study Design: Study Validity: USA Not given Nutrient sampling in tea Medium Key Points: Water fluoride levels ranged from 31.5µg/100g to 129µg/100g and contributed up to a quarter of the final fluoride content of the tea. The fluoride content of the tea was closely related to the fluoride content of the water. Brewed caffeinated teas had higher fluoride content than brewed decaffeinated teas. Microwave brewed teas had lower fluoride content than cup brewed teas (using boiled water). Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD 65

66 Strengths: Wide range of samples of both tea and water sampled Systematic sample to cover population zones across the country Brewing and microwave process uniform for testing of all samples Limitations: Did not test level of absorption. Can the findings be generalised? NO Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO: the study did not state whether using fluoridated water to brew tea led to recommended daily intake of fluoride being exceeded. NONE 66

67 [23*] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Study type: Location of Study: Time of Study: Study Validity: Perspectives in the Effective Use of Fluoride in Asia Petersen PE, Phantumvanit P Journal of Dental Research (119) Not given Oral and Public Health Epidemiology Dental caries is the most prevalent chronic disease affecting human populations worldwide. The diverse disease patterns across and within countries are related to socio-behavioural determinants, demographic factors, environmental conditions, and the availability and accessibility of oral health services, in particular, exposure to disease prevention programs (Petersen, 2003, 2008a). Benefits of fluoride for caries prevention have been substantiated in many countries (Petersen and Lennon, 2004; Jones et al., 2005). In the second half of the 20(th) century, this focus shifted to the development and evaluation of fluoride toothpastes and rinses and, to a lesser extent, to alternatives to water fluoridation, such as salt and milk fluoridation. Most recently, efforts have been made to summarize this extensive database through systematic reviews of fluoride administration (McDonagh et al., 2000; Marinho et al., 2003; Australian Government, 2007). The Asian workshop held in Phan-Nga, Thailand, during March 22-24, 2011, aimed to discuss current information on fluoride and dental caries, as well as to try identifying barriers and opportunities that countries of Asia may have for implementing such programs. In addition, the intention was to give recommendations for including fluoride schemes within national public health programs. N/A Discussion Paper Phang-Nga, Thailand 2011 N/A discussion paper Key Points: Delegates to a workshop acknowledged the need for preliminary studies on fluoride exposure before introducing community fluoridation programmes Delegates also acknowledged the trade-off between caries prevention and dental fluorosis Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Limitations: N/A - Discussion paper N/A N/A N/A N/A Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? LIMITED due to focus on low to middle income countries; NO 67

68 Implications for the Ministry of Health water fluoridation policy: NONE 68

69 [24*] Date: November 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): A comparative study of the IQ of children age 7-8in a high and low fluoride water city in Iran Poureslami HR, Horri A, Garrus B, Fluoride (3) Oral and Public Health Epidemiology Summary of Study: Abstract: A study was conducted to evaluate the effect of high and low fluoride (F) in the drinking water on the Intelligence Quotient (IQ) of young schoolchildren in two otherwise similar high-altitude communities in a mountainous region of Kerman Province, Iran. The study sample consisted of 120 boys and girls age 7-9: 60 in the city of Koohbanan (pop. 12,253; elev. 2200m) with 2.38ppm F in the water and 60 in the city of Baft (pop. 14,628; elev m) with 0.41ppm F in the water. Using a Persian version of Raven's Progressive Matrices Intelligence Test, the mean IQ scores of the children in low F Baft was ± , and in high F Koohbanan it was significantly lower at ± (p = 0.028). Kerman Province, Iran Study Location: Not given Study Dates: Cross-sectional study Type of Study: Low Validity of Study: Key Points: Mean IQ was statistically significantly lower in the high fluoride area compared to the low fluoride area The difference in IQ between the two areas was statistically significant for boys only. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: FAIR FAIR Limitations: Low sample size Limited relevance given the study took place in area with endemic fluorosis and naturally high fluoride concentration in groundwater No control for confounding factors such as socioeconomic status, parental educational achievement etc. Can the findings be generalised? NO specific to the climatic and geological conditions of the area Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation NO NONE 69

70 policy: [25*] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Tea fluoride consumption and the paediatric patient Quock RL, Gao JX, Chan JT Food Chemistry Oral and Public Health Epidemiology The purpose of this study was to measure the fluoride concentrations of various commercially available tea infusions, with a specific focus on risk of fluorosis. 100 ml infusions of 43 different tea brands were kept at a constant temperature of 85 C and measured for fluoride concentration at 5, 15, 30, 60, and 120min using a fluoride ion-specific electrode and millivolt meter. After 5 min at 85 C mean fluoride concentration, in μg/ml with standard deviation, was 2.08 ± 1.24 for caffeinated tea infusions, 4.38 ± 0.97 for decaffeinated tea infusions, and 0.05 ± 0.02 for herbal teas. Caffeinated teas derived from the traditional source, Camellia sinensis, demonstrated significantly higher concentrations of fluoride than herbal teas (p < 0.01). Furthermore, decaffeinated teas demonstrated significantly higher concentrations of fluoride than caffeinated teas (p < 0.01). Some tea infusions may place a paediatric patient at higher risk for fluorosis if consumed as the primary source of hydration. Study Location: Study Dates: Study Design: Study validity: Houston, Texas, USA Not given nutrient sampling in tea low-medium Key Points: 43 brands of tea were tested at different periods of infusion in boiled, distilled water to calculate fluoride concentration. Decaffeinated tea ( µg/ml av. conc. 4.38µg/ml) had the highest fluoride concentration, followed by caffeinated tea ( µg/ml av. conc. 2.8µg/ml), with herbal teas having the lowest fluoride concentration ( µg/ml, av. conc. 0.05µg/ml). All (non-herbal) teas met or exceeded the recommended fluoride concentration of water µg/ml. 26/32 teas exceeded the recommended optimal fluoride concentration in water stated above whilst 19/26 teas exceeded the maximum water fluoride concentration of 2µg/ml. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR 70

71 Strengths: Process of brewing tea uniform Effect of strength of tea tested (using period of infusion) Limitations: Did not test level of absorption. Can the findings be generalised? The discussion and conclusion highlights paediatric tea drinkers as at possible risk of fluorosis but does not identify the size of this group or the degree of potential impact on it. Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 71

72 [26] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Comparison of Enamel Defects in Primary and Permanent Dentition of Children from a Low Fluoride District of Australia Seow WK, Ford D, Kazouillis S, Newman B, Holcombe T Paediatric Dentistry (3) Oral and Public Health Epidemiology Purpose: The purpose of this study was to compare developmental defects of enamel (DDE) in the primary and permanent dentitions of children from a low-fluoride district. Methods: A total of 517 healthy schoolchildren were examined using the modified DDE criteria. Results: The prevalence of DDE in the primary and permanent dentition was 25% and 58%, respectively (P<.001). The mean number of teeth with enamel opacity per subject was approximately threefold compared to that affected by enamel hypoplasia (3.1 ± 3.8 vs 0.8 ± 1.4, P<.001 in the primary dentition and 3.6 ± 4.7 vs 1.2 ± 22, P<.001 in the permanent dentition). Demarcated opacities (83%) were predominant compared to diffuse opacities (17%), while missing enamel was the most common type of enamel hypoplasia (50%), followed by grooves (31%) and enamel pits (19%) (P=.04). In the permanent dentition, diffuse and demarcated opacities were equally frequent, while enamel grooves were the commonest type of hypoplasia (52%), followed by missing enamel (35%) and enamel pits (5%; P<.001). Conclusions: In a low-fluoride community, developmental defects of enamel were twice as common in the permanent dentition vs the primary dentition. In the primary dentition, the predominant defects were demarcated opacities and missing enamel, while in the permanent dentition, the defects were more variable. Study Location: Study Dates: Study Type: Study Validity: Queensland, Australia Not given Cross-sectional study Medium Key Points: 47% of children examined had developmental defects of the enamel (DDE) on at least one tooth surface. (25% on primary dentition, 58% on permanent dentition). Of the DDE, 33% (15% for primary dentition, 41% for secondary dentition) of children had opacities (transparency, associated with dental fluorosis) whilst 15% had enamel hypoplasia (missing enamel, grooves, lesions etc.). The proportion of enamel opacities was similar to that in communities with water fluoride levels of 0.7-1ppm. The study authors suggested reasons other than water fluoride content for the presence of opacities, which included: fluoride from food and beverages or swallowing toothpaste, illness or infection (including treatments with certain antibiotics) during the tooth development stage. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? GOOD 72

73 The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Cross sectional study using primary data Inter and Intra examiner calibration Limitations: No comparison group, especially from an area with high water fluoride concentration Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: The authors suggest that enamel opacities in children may occur due to factors other than water fluoride content level: It is interesting to note that, in the present study, despite the lack of fluoridation in community water supplies, the prevalence rate of diffuse opacities of approximately 49% in permanent dentition is similar to those observed in communities with levels of optimally fluoridated water of approximately 0.7 to 1 ppm. These findings suggest that the children in the present study may have consumed other sources of systemic fluoride, such as toothpaste or foods and beverages manufactured using fluoridated water 73

74 [27*] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: The Relationship between dental fluorosis and intelligence quotient in school children of Bagalkot district Shivaprakash PK, Ohri K, Noorani H Journal of the Indian Society of Pedontics and Preventative Dentistry Oral and Public Health Epidemiology This study was conducted on 160 children, in the Bagalkot district of Karnataka state between August and October 2010, with the aim of finding out if there is a relation between dental fluorosis status and Intelligence Quotient (IQ). Children were categorized as, those suffering from dental fluorosis and those not suffering from dental fluorosis and for all children in both categories, Intelligence testing was done using the Raven's Coloured Progressive Matrices. The following observations were made from the data gathered: The mean IQ score of children without dental fluorosis was significantly higher than those children who had dental fluorosis. The mean IQ scores did not vary with the severity of dental fluorosis as classified by Dean's fluorosis index. Also it was noticed that the percentage of children with dental fluorosis was more in Extremely Low and Low IQ categories whereas the percentage of children without dental fluorosis was more in Average and High Average IQ categories. Previous studies had indicated toward decreased Intelligence in children exposed to high levels of fluoride and our study also confirmed such an effect. Study Location: Study Dates: Study Type: Study Validity: Bagalkot District, Kamataka State, India August-October 2010 Cross-sectional study Low Key Points: The study involved measuring the Intelligence Quotient (IQ) of 7-11 year olds living in two communities in Bagalkot district, one with a high groundwater fluoride content (<0.5ppm) and one with a high groundwater fluoride content ( ppm). The study included 80 children who did not have dental fluorosis from 120 randomly selected children from the low fluoride area, and 80 children who did have dental fluorosis from 150 randomly selected children from the high fluoride area. The mean IQ was for children with dental fluorosis which was statistically significantly lower than the mean IQ of for children without dental fluorosis. 72.5% of children with dental fluorosis had extremely low or borderline IQ compared to 47.5% of children without fluorosis % of children with dental fluorosis had average or high average IQ scores compared to 28.75% of children without fluorosis. The authors concluded: The results of our research show that exposure to high levels of fluoride, as also determined by the dental fluorosis status of the child, does have detrimental effect on the mental ability of the child. Although the effect on the IQ of the child does not seem to be affected by the degree of fluorosis, nevertheless there is a correlation between dental fluorosis and the intellectual ability. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is 74

75 appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR Strengths: Cross-sectional study using random sampling methods The following factors were controlled for: all children were permanent residents of their area, none of the children had had head trauma, and all children were of normal birth weight. Limitations: No comparison of IQ between fluorosis and non-fluorosis sufferers from within each of the two sample populations. Can the findings be generalised? NO Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: No comparison of IQ between the whole sample populations between the two areas (regardless of fluorosis status). No control for other potential confounding factors (eg, parental education, socioeconomic status). NO, the samples contained naturally occurring fluoride in groundwater, which (in the high fluoride area) where times the level to which water is fluoridated in New Zealand NONE 75

76 [28*] Date: November 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Study Location: Study Dates: Type of Study: Study Validity: Prevalence of dental disease in 5-14 year old school children in rural areas of the Barabanki district, Uttar Pradesh, India Singh M, Saint A, Saimbi CS, Baipai AK Indian Journal of Dental Research (3) Oral and Public Health Epidemiology Background: Epidemiological studies are helpful in planning and implementing oral health programs in a given population. This initiative is a consequence of the absence of any information on any study being conducted in the past on the prevalence of dental diseases in the Barabanki district of Uttar Pradesh (UP). Aims: The aims were to (1) assess the prevalence of gingivitis, fluorosis, and malocclusion in the school-going children of rural areas of district Barabanki and (2) evaluate the pattern of above-mentioned diseases in different age groups and genders. Materials and Methods: A total of 836 school-going children comprising 430 boys and 406 girls were examined. A total of 238 children were in the age group of 5-7 years. A total of 277 and 321 children were in the age groups of 8-10 and years, respectively. Statistical Analysis: A chi-square test was used for deriving results. Results: The prevalence of gingivitis, fluorosis, and malocclusion was 78.35%, 33.37%, and 34.09%, respectively. The difference between age groups for the prevalence of gingivitis was highly significant, and was more among girls as compared to boys. A significant increase in the prevalence of malocclusion was observed with age. No significant difference was found among genders for the prevalence of malocclusion. An increase in the prevalence of fluorosis was highly significant with age. The difference in fluorosis was insignificant between boys and girls. Uttar Pradesh, India January April 2010 Prevalence Study Low Key Points: Prevalence of gingivitis was high (78.35%) and increases with age. It is statistically significantly lower amongst boys (74.65%) than girls (82.26%). Prevalence of malocclusion was 34.09%. There was no statistically significant difference in the prevalence between girls (35.46%) and boys (32.79%). It was also higher in permanent teeth compared to deciduous teeth. Prevalence of fluorosis was 33.37%, but there was no statistically significant difference in prevalence between boys (34.42%) and girls (32.27%). Average fluoride concentration was 1.2ppm. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the GOOD GOOD CONCLUSION NOT STATED 76

77 initial hypothesis/aim? CONCLUSION NOT STATED Strengths: Single examiner provided consistency Random selection method used Average water fluoride level was slightly higher than that used in New Zealand but within the WHO recommended range, Limitations: Socioeconomic status was determined using school type and location rather than at individual level. Residential history and other potential influencing factors were not elicited. Did not directly investigate if the findings were results of effect of fluoride (occurring naturally in the water supply). Can the findings be generalised? Limited application as did not investigation the possible effects of fluoride in the water supply Focused only dental health results Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 77

78 [29] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Effect of health promotion and fluoride varnish on dental caries amongst Australian Aboriginal children: results from a community randomised control trial Slade GD, Ballie RS, Roberts Thomson K, Kaye I, Endean C, Simmons B, Morris P. Community Dentistry and Oral Epidemiology Oral and Public Health Epidemiology Objectives: We tested a dental health program in remote Aboriginal communities of Australia's Northern Territory, hypothesizing that it would reduce dental caries in preschool children. Methods: In this 2-year, prospective, cluster-randomized, concurrent controlled, open trial of the dental health program compared to no such program, 30 communities were allocated at random to intervention and control groups. All residents aged months were invited to participate. Twice per year for 2 years in the 15 intervention communities, fluoride varnish was applied to children's teeth, water consumption and daily tooth cleaning with toothpaste were advocated, dental health was promoted in community settings, and primary health care workers were trained in preventive dental care. Data from dental examinations at baseline and after 2 years were used to compute net dental caries increment per child (dmfs). A multi-level statistical model compared dmfs between intervention and control groups with adjustment for the clustered randomization design; four other models used additional variables for adjustment. Results: At baseline, 666 children were examined; 543 of them (82%) were re-examined 2 years later. The adjusted dmfs increment was significantly lower in the intervention group compared to the control group by an average of 3.0 surfaces per child (95% CI = 1.2, 4.9), a prevented fraction of 31%. Adjustment for additional variables yielded caries reductions ranging from 2.3 to 3.5 surfaces per child and prevented fractions of 24-36%. Conclusions: These results corroborate findings from other studies where fluoride varnish was efficacious in preventing dental caries in young children. Study Location: Study Dates: Type of Study: Study Validity: Key Points: Northern Territory Australia May 2006-December 2008 Community randomised control trial Medium Caries is endemic in the intervention and control populations. At the baseline assessment, 61% of children in the intervention group and 64% of children in the control group had caries. The adjusted dmfs increment was significantly lower in the intervention group compared to the control group by an average of 3.0 surfaces per child (95% CI = 1.2, 4.9), a prevented fraction of 31%. The difference in the severity of caries between the intervention and control groups was statistically significant. Children in the intervention group had an average of 3.0 fewer dmfs than the children in the control group. When water fluoridation was controlled for the difference increased to an average of 3.5 fewer dmfs. 5 of the 15 communities in the control group and 3 of the 15 communities in the intervention group had water fluoride concentrations of greater than or equal to 0.6ppm. Water fluoridation had a statistically significant impact on the number of dmfs that was independent of the intervention. An increase of 1ppm F in drinking water was associated with an average reduction of 4.3 carious surfaces, per child. As the authors noted: although that is an observed association, not a finding from a randomized treatment allocation, the implication is that a nonfluoridated community that adopted this 78

79 Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR GOOD intervention and increased concentration of fluoride in its water supply to 1ppm F could expect an average reduction of = 7.8 fewer carious surfaces, per child more than halving the caries rate. Strengths: Community based prospective randomised control trial. Capacity building used to gain community support Rigorous calibration of examination methods, aided inter-examiner reliability. Limitations: Sample size calculation used Northern Territory 4 year olds of all ethnic groups while the study itself was based solely in NT Australian Aboriginal communities. A larger proportion of the control population (19%) lived in communities with greater than or equal 0.6ppm water fluoride content compared to the intervention population (8%). The single impact of fluoride varnish could not be isolated as the study also included public health education on dental care. Children received between 0-8 varnish applications, but were not allocated to different varnish frequency groups Can the findings be generalised? To similar communities only, i.e. indigenous populations in Australia where caries are endemic in the population Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Water fluoridation can reduce dental caries in preschool children in endemic caries, rural, indigenous communities both in concurrence with and independent of other interventions. 79

80 [30*] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Study type: Location of Study: Time of Study: Study Validity: Key Points: Caries preventive and remineralising effect of fluoride gel in orthodontic patients after 2 years Splieth CH, Teuner A, Gedrange T, Berndt C Clinical Oral Invest Not given Not given Oral and Public Health Epidemiology Patients with orthodontic appliances exhibit a higher caries risk, but they are often excluded from preventive studies. Thus, the aim of this observational study was to assess the cariespreventive and remineralising effect of a high-fluoride gel in orthodontic patients. Two hundred twenty-one orthodontic patients (age, 6-19 years; mean, 13.1 ± 2.3; n = 104 with use of a 1.25% fluoride gel weekly at home, 117 participants without) were recruited and followed for 2 years, recording caries (decayed/missing/filled teeth (DMFT)/decayed /missing /filled surface (DMFS), active/inactive lesions), orthodontic treatment, use of fluorides, plaque and gingivitis. Baseline values regarding demographic and clinical parameters were equivalent for the 75 participants using fluoride gel and the 77 individuals of the control group who completed the study. The initial plaque and gingivitis values (proximal plaque index (API), 37% ± 34 and 42% ± 39, resp.; papillary bleeding index (PBI), 19% ± 28 and 22% ± 27, resp.) deteriorated slightly during the 2-year study (API, 54%/56%; PBI, 25%/28%). The increase in carious defects or fillings was minimal in both groups (fluoride, 0.75 DMFT ± 1.2, 1.27 DMFS ± 1.9; control, 0.99 ± 1.3 and 1.62 ± 2.6, resp.) without reaching statistical significance (p = 0.12 for DMFT, 0.44 for DMFS). The main statistically significant effect of the fluoride use was the reversal of active initial lesions diagnosed (fluoride group, ± 1.82; control, ± 2.0, p = 0.004), while the number of inactive initial lesions increased (2.3 ± 2.1 and 1.7 ± 2.1, resp.; p = 0.02). In conclusion, the weekly application of a fluoride gel in orthodontic patients can reduce their caries activity. Initial caries lesions in orthodontic patients can be inactivated by weekly fluoride gel use at home. Prospective Observational Study Griefswald, Germany Low The main statistically significant effect of the fluoride use was the reversal of active initial lesions diagnosed (fluoride group, ± 1.82; control, ± 2.0, p = 0.004), while the number of inactive initial lesions increased (2.3 ± 2.1 and 1.7 ± 2.1, resp.; p = 0.02). Orthodontic patients who used fluoride gel at home, in addition to tooth brushing, had a smaller increase in DMFS compared to a control group (4.0 ± 4.8, compared to 4.8 ±6.0) Orthodontic patients using fluoride gel also had a statistically significant greater reduction in carious lesions than the control group(1.4 ± 1.9 to 0.5 ± 0.8 compared to 1.6 ± 2.0 to 1.4 ± 2.0) The study showed that: the weekly application of a fluoride gel in orthodontic patients can reduce their caries activity. Initial caries lesions in orthodontic patients can be inactivated by weekly fluoride gel use at home. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is 80

81 appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD GOOD Strengths: Prospective study allowing individual follow up from baseline Limitations: Relatively with a high drop-out rate (31%) Can the findings be generalised? NO The control group had a higher baseline score for DMFS compared to the intervention group. Confidence intervals were wide for both groups Drop-out was bias towards non-compliant subjects Continued fall in caries prevalence in Germany (including during the course of the study) makes statistically significant differences in DMFS almost impossible to predict Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 81

82 [31] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Cochrane Reviews on the Benefits/ Risks of Fluoride Toothpastes Wong MCM, Clarkson J, Glenny A-M, Lo ECM, Marinho VCC, Tsang BWK, Walsh T, Worthington HV Journal of Dental Research Oral and Public Health This concise review presents two Cochrane Reviews undertaken to determine: (1) the relative effectiveness of fluoride toothpastes of different concentrations in preventing dental caries in children and adolescents; and (2) the relationship between the use of topical fluorides in young children and their risk of developing dental fluorosis. To determine the relative effectiveness of fluoride toothpastes of different concentrations, we undertook a network meta-analysis utilizing both direct and indirect comparisons from randomized controlled trials (RCTs). The review examining fluorosis included evidence from experimental and observational studies. The findings of the reviews confirm the benefits of using fluoride toothpaste, when compared with placebo, in preventing caries in children and adolescents, but only significantly for fluoride concentrations of 1000ppm and above. The relative cariespreventive effects of fluoride toothpastes of different concentrations increase with higher fluoride concentration. However, there is weak, unreliable evidence that starting the use of fluoride toothpaste in children under 12 months of age may be associated with an increased risk of fluorosis. The decision of what fluoride levels to use for children under 6 years should be balanced between the risk of developing dental caries and that of mild fluorosis. Study Location: Study Dates: Study Type: Study Validity: Various 2010 Cochrane Review High Key Points: The paper discusses two reviews with two separate, but linked aims ( The relative effectiveness of fluoride toothpastes at a range of concentrations on dental caries in children and The relationship between the use of topical fluoride treatments in young children and the risk of developing dental fluorosis ) Aim 1 Randomised Control Trials are used to analyse this aim The paper used a primary fraction (pf) to estimate effects of different concentrations of toothpaste. (pf = (mean increment caries control group mean increment caries intervention group)/mean increment caries control group) Toothpastes with low fluoride concentrations ( ppm) did not demonstrate a statistically significant reduction in dental caries when compared to a placebo. Toothpastes with fluoride concentrations >1000ppm showed a statistically significant reduction in dental caries when compared to a placebo (23%pf, 95%CI 19-27% to 36%pf, 95%CI 27-44%). Toothpastes with a fluoride concentrations> 2400ppm demonstrated a statistically significant reduction in dental caries when compared to toothpastes with low fluoride concentrations of <550ppm, (of 20%pf CI2-38%). Aim 2 A combination randomised controlled trials (RCT), prospective, case control and cross sectional studies are used to analyse this aim Risk Ratios (RR) are used in the analysis of prospective studies and randomise controlled trials studies. Odds Ratios (OR) are used to analyse case control and cross sectional studies. There was a statistically significant reduction in incidence of fluorosis where brushing with fluoride toothpaste occurred after 12 months of age (OR+0.70, 95%CI ) No statistically significant effect was found between incidence of fluorosis and frequency of tooth brushing / amount of toothpaste used. Two RCT s found a statistically significant increase in incidence of fluorosis with 82

83 Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? increased fluoride concentration in toothpaste, however this was not supported when the data was pooled in a meta-analysis. two separate studies were reported on with two separate aims. NA Cochrane Review, data was gathered from previously published studies Strengths: Pooled data covering a wide range of trials over a long period of time Cochrane esteem Limitations: Secondary data is used in both studies Can the findings be generalised? Aim 2 includes a wide range of topical fluoride applications not just toothpaste, effects are not stratified therefore individual effects cannot be distinguished. Too few trials on the impact of toothpastes at different fluoride concentrations on fluorosis incidence have been carried out for valid conclusions to be drawn. Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 83

84 [32*] Date: December 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract Fluoride contamination and fluorosis in Gaya Region of Bihar, India Yasmin S, Monterio S, Ligimo; PA, D Souza D Current Biotica (2) Oral and Public Health Epidemiology This study was conducted to estimate the fluoride level in groundwater and to determine the extent of fluorosis in three selected villages of Gaya Region, Bihar, India, where groundwater is the main source of drinking water. Also, the occurrence of fluorosis was correlated with nutritional aspects of the study subjects. It was evident in the results that the people who live below the poverty line are highly susceptible to fluorosis. Study type: Location of Study: Time of Study: Cross-sectional study Bihar, India Not stated Study Validity: Low Key Points: Fluoride concentrations of up to 14.4mg/L water were found in the water supply in the study area. (mean concentration; mg/L depending on location of sample, variance mg/L, modal concentration of drinking/ cooking water 3-9mg/L) 20 cases of dental fluorosis were identified, 2 of skeletal fluorosis and 24 of joint pain. Those of a higher socio economic status, who consumed a more varied diet (including fresh fruit and vegetables), had lower rates of all conditions. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR POOR QUESTIONABLE- given the limitations listed below NO- conclusions related to social class and diet rather than water fluoride content Strengths: NONE Limitations: Water sampling frequency not stated (may have only been one sample, therefore season, climatic conditions etc. not controlled for) Can the findings be generalised? NO Are the findings applicable to water fluoridation in New Zealand? Results for fluorosis broken down by social class but not by fluoride concentration of water source. NO 84

85 Implications for the Ministry of Health water fluoridation policy: NONE [33] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Caries and fluorosis in the Santiago metropolitan region in Chile: The impact of fluoridation of the water Yevenes I, Zillman G, Munoz A, Aranda W, Echeverria S, Hassl, Maass P, Salazar M Rev. Odonto Cienc (2) Oral and Public Health Epidemiology Purpose: To assess the damage and the prevalence of caries and fluorosis in children and adolescents in the metropolitan area after 8 years of drinking water fluoridation and to compare them with the baseline study. Methods: This was a prevalence study. The sample was selected using two-step probability sampling and stratified according to socioeconomic level. Subjects included 2,323 schoolchildren aged 6 to 8 years and 12 years living within the metropolitan region. The parents of all students provided consent and were previously included in the study. The subjects were clinically examined by calibrated dentists, who used World Health Organization (WHO) screening criteria and indicators to determine the presence of caries and dental fluorosis. Results: No cavity damage was found in 23.68% of the children. The average dmft was 3.18 for children aged 6 to 8 years. The DMFT was 0.59 in children aged 6 to 8 years and 2.6 in children 12 years compared with the baseline study. These differences were statistically significant. There were also significant differences in the DMFT index for each socioeconomic status group. The average number of dmft was higher among children of low socioeconomic status. Of the studied children, 14.3% of children had dental fluorosis. Fluorosis was very mild in 12.35% of the cases, mild in 1.98% and moderate in 0.26%. There were no cases of severe fluorosis (classified according to Dean's index). Conclusion: We conclude that after 8 years drinking water fluoridation in the metropolitan area, the number of children with no history of caries has increased by approximately 100%. The number of cases significantly affected by caries has also decreased significantly. The incidence of dental fluorosis has increased, but to milder degrees. Study Location: Study Dates: Study Type: Study Validity: Santiago, Chile Cross-sectional study Medium Key Points: A prevalence study of cavities and dental fluorosis in year olds and year olds after 8 years of water fluoridation. A baseline was taken from a study from the same city (Santiago) in 1996; the year water fluoridation was introduced. Since 1996 the prevalence of caries in both age groups had declined. In , 25% of 6-8 year olds were caries free compared to 12% in 1996, whilst 22% of 12 year olds were caries free compared to 11% in There was a statistically significant higher rate of dental caries in lower socioeconomic groups. Only 20.9% of 6-8 year olds and 20.3% of 12 year olds were caries free in the low socio economic group compared to 31.9% and 33.3% in the high socioeconomic group. Fluorosis increased following water fluoridation from 4.2% to 32.5% in 6 to 8 year olds and 2.3% % in 12 year olds, but was almost entirely questionable (15.5%) very light (12.6%) or light (3%). There was a statistically significant lower rate of fluorosis in lower socioeconomic groups (23.5%) compared to higher socioeconomic groups (35.9%). Evaluation Criterion: The aim/ hypothesis of the study 85

86 are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR FAIR Strengths: Community based study. based on the assumption that the baseline study in 1996 was of reasonable validity Calibration of examination methods used to ensure inter-examiner reliability. Limitations: Details of the previous (1996) study used as a baseline for this study were not given. Therefore the validity of the comparison cannot be confirmed Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Other, possible addition sources of fluoride are not identified or controlled for. Provides evidence that: Water fluoridation reduces incidence and prevalence of dental caries in children. Dental caries are higher in lower socio economic groups. There is a trade-off between reduced incidence / prevalence of caries and (very mild - mild) dental fluorosis. 86

87 [34*] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Effective Use of Self-care Fluoride Administration in Asia Zero DT, Marinho VCC, Phantumvanit P Advances in Dental Research :16 Not given Oral and Public Health Epidemiology The caries-preventive benefits of fluoride are generally accepted by dental researchers and practicing professionals worldwide. The benefits of fluoride toothpastes and mouth-rinses have been supported by several high-quality systematic reviews. The formulation of a fluoride toothpaste and biological (salivary flow rate) and behavioural factors (brushing frequency, brushing time, post-brushing rinsing practices, timing of brushing, and amount of toothpaste applied) can influence anti-caries efficacy. Fluoride mouth-rinses have simpler formulations and can have better oral fluoride retention profiles than fluoride toothpastes, depending on post-brushing rinsing behaviours. Fluoride continues to be the mainstay of caries control; however, there is still the need to determine the most effective approach for fluoride utilization in children and adults who remain caries-active. Study type: Location of Study: Time of Study: N/A Discussion Paper Phang-Nga, Thailand 2011 Study Validity: N/A Discussion paper Key Points: Fluoride toothpaste is the most widely used method for fluoride delivery in Asia and is estimated to have a caries inhibiting effect of 24% (95% CI 21-28%) on permanent dentition. Mouth-rinse is recommended for those with high caries risk as it is estimated to have a 26% (95% CI 23-30%) preventative effect on caries increment regardless of exposure to water fluoridation Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Limitations: N/A Discussion paper N/A N/A N/A N/A Can the findings be generalised? LIMITED due to focus on low to middle income countries Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of NO NONE 87

88 Health water fluoridation policy: 88

89 Appendix 2: Communication and Community Engagement [35] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Study Location: Study Dates: Study Type: Study Validity: Associations between oral health behaviour and anxiety about water fluoridation and motivation to establish water fluoridation in Japanese residents Furukawa S, Hagiwara Y, Taguchi C, Turumoto A, Kobayashi S Journal of Oral Science Communication and Community Engagement Since 1972, community water fluoridation programs have not been practiced in Japan. Risk perception among the population plays an important role in the implementation of water fluoridation programs. The oral health behaviour of Japanese children has changed, especially due to recent increases among children in the use of fluoridated products and fluoride applications by dentists. The purpose of this study was to examine the associations between oral health behaviour, risk perception, and the desire to implement water fluoridation among Japanese residents. We distributed a questionnaire survey (response rate: 92.8%) to mothers with children aged two or three years (n = 573). There was a correlation between anxiety and level of motivation to implement water fluoridation (Spearman coefficient: 0.355, P < 0.001). Exposure to various fluoride experiences was higher in the "not anxious" group. The motivation level was significantly higher in subjects who had a better understanding of the effectiveness of fluoride, those who used fluoride tooth paste, and those whose children received fluoride applications from dentists. We conclude that increased knowledge of and experience with fluoride might help decrease the perception of risk and increase motivation for implementing water fluoridation among the general public. Tomioka-kanra area, Gunma prefecture, Japan April-September 2010 Knowledge, Attitudes and Behaviour study Medium Key Points: Among the respondents, knowledge of the role of fluoride in preventing dental caries was high (95.3%), however knowledge of water fluoridation was much lower 47.3%. Use of fluoridated toothpaste was higher amongst adults (76%) than children (70.7%). Motivation (support) for water fluoridation was higher amongst mothers who had knowledge of the effectiveness of fluoride in preventing dental caries. 62.3% of mothers had some concern about water fluoridation Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR 89

90 Strengths: The study was community based using primary data collected by questionnaire from a parent The response rate was very high (92.8%). Limitations: The study was conducted in an area were the benefits of fluoride and water fluoridation were already being promoted Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: There was no controlling for influencing factors (such as socioeconomic status) Continued promotion of water fluoridation increases awareness and support for it. Specific concerns regarding water fluoridation need to be addressed in promotional material. The authors concluded: that increased knowledge of and experience with fluoride might help decrease the perception of risk and increase motivation (support) for implementing water fluoridation among the general public. 90

91 [36] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract Study type: Location of Study: Time of Study: Study Validity: Key Points: Is the use of fluoride toothpaste optimal? Knowledge, attitudes, and behaviour concerning fluoride toothpaste and tooth-brushing in different age groups in Sweden Jensen O, Gabre P, Skőld M, Birkhed D Community Dentistry and Oral Epidemiology 2011 Not given Not given Communication and Community Engagement Objectives: The most effective method to prevent caries is the regular use of fluoride toothpaste. The aim of this study was to evaluate self-care routines in a population by identifying knowledge, attitudes and behaviour relating to fluoride toothpaste and toothbrushing habits. Methods: A questionnaire was sent to 3200 individuals in two municipalities in Sweden. Four age groups representing different life stages were chosen: 15-16, 31-35, and years of age. The participants were selected from the population register by random selection of birth dates. Results: Totally 2023 (63%) individuals answered the questionnaire. The majority (84-94%) in all age groups brushed their teeth twice a day or more often. Good toothpaste behaviour identified as brushing at least twice a day, using at least 1cm toothpaste, brushing 2minutes or longer and using a small amount of water when rinsing was reported by only 10% of the respondents. The factors that increased the odds for having good caries-preventive behaviour were: (i) being female, (ii) being younger than 35 years, (iii) having knowledge about fluoride, (iv) finding use of fluoride toothpaste important and (v) rating own oral health as good. Conclusions: The population seems to have embraced regular tooth-brushing with fluoride toothpaste to a large extent. However, regarding techniques for using fluoride toothpaste effectively, there was great potential for improvement, especially among the older respondents. Knowledge, Attitudes and Behaviour study Uksteningsund and Enkőping, Sweden Not stated Medium Only 10 % of respondents to the study were identified as having good tooth brushing behaviour (these were most likely to be female, over 35 years old and with a good knowledge of fluoride. Most individuals believed that the effect of fluoride in toothpaste was to strengthen teeth. Fluoride knowledge was greatest amongst older participants to the study. 20% of adolescents did not know whether the toothpaste they used contained fluoride. No correlation was found between level of education (as an indicator of socioeconomic status) and tooth brushing habits. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? GOOD 91

92 The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Large study population (n=2023) Relatively high response rate (63%) Random sampling methods used Verification of transmitted data was undertaken Limitations: Oral health behaviour was self-reported therefore chance of recall and response bias (especially among young people, who may be least likely to return the questionnaire). Frequency of responses varied between age groups and sexes Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Identifies the need to improve public knowledge of the effects of fluoride: Increased the odds for having good caries-preventive behaviour included: finding use of fluoride toothpaste important 92

93 [37] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Study type: Location of Study: Time of Study: Validity of Study: Tap or Bottled Water: Drinking Preferences Among Urban Minority Children and Adolescents Huerta-Saenz L, Irigoyen M, Benavides J, Mendoza M Journal of Community Health Communication and Community Engagement The last decade has seen an increasing trend in consumer preference of bottled water over tap water. Little is known what type of water children and adolescents prefer for drinking and what their parents think of their community tap water. The study objective was to assess drinking water preferences, perceptions of the qualities of tap water and bottled water, and fluoride knowledge in an urban paediatric population. We conducted an anonymous survey of a convenience sample of caretakers of children and adolescents at an urban clinic regarding their preferences for tap or bottled water, their perceptions of the quality of tap and bottled water and their knowledge of fluoride. Of the 208 participants (79% African American, 9% Latino), 59% drank tap water, 80% bottled water. Only 17% drank tap water exclusively, 38% drank bottled water exclusively, 42% drank both. We found no significant differences in water preferences across age groups, from infancy to adulthood, or among ethnic groups. Ratings for taste, clarity, purity and safety were significantly higher for bottled water than tap water (P<0.001). Only 24% were aware of fluoride in drinking water. We conclude bottled water was preferred over tap water in an urban minority paediatric population. Perceptions of the qualities of water seemed to drive drinking preferences. Public health strategies are needed to increase public awareness of the impact of bottled water consumption on oral health, household budgets and the environment. Knowledge, Attitudes and Behaviour study USA February May 2009 Low (in application to a New Zealand population) Key Points: Only 24% of those surveyed where aware of whether the bottled/ tap water they used was fluoridated or not. Bottled water was the drink of choice in the population studies (urban African- Americans). This was partly due to a lack of trust in the safety and purity of tap water. A third of those who used tap water filtered it, which might affect the fluoride content. Use of bottled water, which contained minimum water fluoride content) reduces the impact of community water fluoridation programmes in reducing tooth decay. Use of bottled water also makes it more difficult to assess whether fluoride supplements are necessary. The majority of parents in the study used bottled water to make up infant formula (this is recommended by the CDC in the USA due to concerns over safety and the risk of dental fluorosis) Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the FAIR 93

94 conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: Primary data used Limitations: Convenience sample was used Can the findings be generalised? NO The sample population was mainly African-American and the authors indicate that the results can therefore not be generalised. Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO- because findings cannot be generalised. However they raise some issues regarding the use of bottled and filtered water as opposed to the use of tap water in New Zealand. This may impact on the effectiveness of water fluoridation programmes. NONE 94

95 [38*] Date: January 2012 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Community-oriented Administration of Fluoride for the Prevention of Dental Caries: A Summary of the current situation in Asia Petersen PE, Baez RJ, Lennon MA Advances in Dental Research (5) Not given Communication and Community Engagement Dental caries is the most prevalent chronic disease affecting human populations around the world. It is recognized that fluoride plays a significant role in dental caries reduction. Meanwhile, several low- and middle-income countries of Asia have not yet implemented systematic fluoride programs; contributing factors relate to misconceptions about the mechanisms of fluoride, low priority given to oral health in national health policy and strategic plans, and lack of interest among public health administrators. A workshop on the effective use of fluoride in Asia took place in Phang-Nga, Thailand, in A series of country presentations addressed some of the topics mentioned above; in addition, speakers from countries of the region provided examples of successful fluoride interventions and discussed program limitations, barriers encountered, and solutions, as well as possibilities for expanding coverage. Participants acknowledged that automatic fluoridation through water, salt, and milk is the most effective and equitable strategy for the prevention of dental caries. Concerns were expressed that government-subsidized community fluoride prevention programs may face privatization. In addition, the use of affordable fluoride-containing toothpastes should be encouraged. The workshop identified: strengths and weaknesses of on-going community-based fluoride programs, as well as the interest of countries in a particular method; the requirement for World Health Organization (WHO) technical assistance on various aspects, including fluoridation process, feasibility studies, and implementation of effective epidemiological surveillance of the program; exchange of information; and the need for inter-country collaboration. It was acknowledged that program process and evaluation at the local and country levels need further dissemination. The meeting was co-sponsored by the World Health Organization, the International Association for Dental Research, and the World Dental Federation. N/A Discussion Paper Study type: Location of Study: Time of Study: Study Validity: Key Points: Phang-Nga, Thailand 2011 N/A Discussion Paper Participants in a workshop on the effective use of fluoride in Asia identified the automatic fluoridation of water, salt or milk as the most efficient and equitable strategy for the prevention of dental caries. The need for affordable fluoride toothpaste was also acknowledged. Malaysia, Singapore, Vietnam, Brunei, Hong Kong and some parts of China have had extensive water fluoridation programmes since the 1950 s Challenges to the effectiveness of water fluoridation in the region have come from: increased use of bottled and filtered water; increased use of fluoridated toothpaste leading to a reduction in water fluoride concentration in Singapore from 0.7 to 0.5 mg/l due to concerns around dental fluorosis Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? N/A discussion paper 95

96 The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: N/A N/A N/A N/A Limitations: Can the findings be generalised? LIMITED due to focus on low to middle income countries Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Raises awareness over consumer preferences for bottled water and the impact of this on adequate daily intake of fluoride (to prevent dental caries). Raises awareness of public concerns regarding dental fluorosis 96

97 [39*] Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Inconsistencies in recommendations on oral hygiene practices for children by professional dental and paediatric organisations in 10 countries Pires dos Santos AP, Nadanovsky P, Heloisa de Oliveira B International Journal of Paediactric Dentistry Communication Background. Some of the basic dental health practices that are recommended to the public by professionals are not evidence based. Incorrect oral health messages may adversely affect children's oral health behaviours. Aim. To identify and list the recommendations concerning children's oral hygiene practices provided by dental and paediatric organisations, and to assess how these recommendations relate to the scientific evidence currently available. Design. Cross-sectional. The authors contacted professional organisations in ten countries requesting items (brochures, leaflets or folders) containing messages on children's oral hygiene practices. They then listed these recommendations and assessed how they related to scientific evidence obtained from systematic reviews available at PubMed and the Cochrane Library. Results. Fifty-two of 59 (88%) organisations responded to our request and 24 dental health education materials were submitted to the authors. They mentioned recommendations on oral hygiene practices for children, such as tooth brushing frequency, supervision and technique; when to start and how long tooth brushing should last; toothbrush design and replacement; flossing; gums/teeth wiping; tongue cleaning; type and amount of toothpaste and advice on toothpaste ingestion. The search at PubMed and the Cochrane Library resulted in 11 systematic reviews addressing these topics. Conclusions. Several oral hygiene messages delivered by professional organisations showed inconsistencies and lacked scientific support. Study Location: Study Dates: Study Type: Study Validity: Rio de Janeriro, Brazil using information from: Australia, Brazil, Canada, Denmark, Finland, Japan, Norway, Sweden, UK, USA September 2008-January 2010 Cross sectional study Low Key Points: Recommendations on oral hygiene are not consistent across different organisations and although some are in line with best currently available scientific evidence, most lack scientific support. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? FAIR No specific conclusion stated NO Strengths: High response rate (88%) from organisations involved in giving paediatric oral hygiene advice 97

98 Limitations: No attempt was made to draw a representative sample of national and international organisations Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: Comparisons were not made across countries despite the organisations representing 10 different countries. The paper was more of a discussion of the material received than an analysis of it. NO NONE 98

99 [40*] Date: November 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Assessment of Paediatric Dental Knowledge in Jeddah, Saudi Arabia Sabbagh HJ, El-Kateb M, Al Nowaisser A, Hanno AG, Alamoudi NH Journal of Clinical Paediatric Dentistry Communication and Community Engagement Early assessment of the oral health status of children has the potential to reduce or even eliminate oral diseases. Parents rarely take their children to dentist early enough to control dental diseases. However, parents contact paediatricians several times even before the child is born and during the child's early life. Accordingly, paediatricians are considered a perfect and reliable source for oral health control and prevention. Aim: To measure the dental knowledge, attitude and behaviour (KAB) of paediatricians in the City of Jeddah regarding oral health status and methods for prevention of dental diseases in children. Materials and method: Questionnaires consisting of 40 demographic and KAB's questions were distributed to all paediatricians in Jeddah city (605 paediatricians). The KABs' questions consisted of general dental knowledge, preventive dental measures, timing for referral, diet counselling, para-functional habits and handling of traumatized teeth. A score was given for each question. Percentages of total scores of KABs were compared. Results: The response rate of paediatricians in Jeddah city (363) was 60%. Their mean age was years. Paediatricians KABs were found to be unsatisfactory. The most important observation was that the concept of oral health prevention was deficient. Paediatricians awareness of fissure sealants, fluoride, dietary counselling, time of first dental visits and thumb sucking were quite limited. Paediatricians knowledge was significantly lower than their attitude and behaviour s scores. Conclusion: In general, paediatricians knowledge, attitudes and behaviour regarding oral health were not satisfactory. Study Location: Study Dates: Type of Study: Study Validity Key Points: Jeddah, Saudi Arabia Not given Qualitative Study Low The prevalence of dental caries in Saudi Arabia is high, increasing from 74% to 96% in the past decade.) Only 9% paediatricians knew that fluoride concentration in drinking water needed to be considered before prescribing fluoride supplements. Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? GOOD GOOD 99

100 Strengths: Comprehensive questionnaire Limitations: Response rate was 60% Very limited relevance to New Zealand Can the findings be generalised? NO dependent on training/ health care system Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 100

101 Appendix 3: Other: Health Economics [41] Date: December 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract Water Fluoridation Costs in Texas: Texas Health STEPS (EPISDT-Medicaid) Lopez J.A. Masters Abstract 2011 Not given Not given Other: Health Economics Dental caries lead to children being less ready to learn and results in diminished productivity in the classroom. Tooth decay causes pain and infection, leading to impaired chewing, speech, and facial expression, in addition to a loss in self-esteem. There have been many studies supporting the safety and efficacy of community water fluoridation in reducing dental caries. Water fluoridation has been identified by the Centres for Disease Control and Prevention as one of 10 great public health achievements of the 20th century. The decline in the prevalence and severity of tooth decay in the United States during the past 60 years has been attributed largely to the increased use of fluoride; in particular, the widespread utilization of community water fluoridation. However, in the decades since fluoridation was first introduced, reductions in dental caries have declined, most likely due to the presence of other sources of fluoride. Questions have been raised regarding the need to continue to fluoridate community water supplies in the face of possible excessive exposure to fluoride. Nevertheless, dental caries continue to be a significant public health burden throughout the world, including the United States, especially among low-income and disadvantaged populations. Although many poor children receive their dental care through Medicaid, the percentage of Texas children with untreated dental caries continues to exceed the U. S. average and is well above Healthy People 2010 goals, even as state Medicaid expenditures continue to rise. The objective of this study is to determine the relationship between Medicaid dental expenditures and community water fluoridation levels in Texas counties. By examining this relationship, the cost-effectiveness of community water fluoridation in the Texas paediatric Medicaid beneficiary population, as measured by publicly financed dental care expenditures, may be ascertained. Study type: Location of Study: Time of Study: Study Validity: Key Points: Economic Analysis Texas, USA Medium The study examines the impact of one public health policy water fluoridation on another Medicaid (dental claims for children 1-20 years) 80% of Medicaid dental costs are for the examination for and the prevention and treatment of dental caries. Optimal water fluoridation level (in economic terms) was identified as 0.8ppm. Cost savings were calculated using optimal, actual and observed methods of calculation, these three methods identified cost savings of $18-$20(US) per child per year, (leading to a 16% reduction in Medicaid cost for dental treatment). Cost savings varied between counties according to the size of the population, and proportion of the children (aged 1-20 years) enrolled in the Medicaid STEPS programme. Using the above, it was calculated that the cost of installing and maintaining water fluoridation infrastructure would be recouped in 2-7 years. 101

102 Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: GOOD GOOD Limitations: Medicaid is limited to low socioeconomic status children, who are identified as more at risk of dental caries. Therefore cost savings might be greater than for a more general population Can the findings be generalised? Only to the USA Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: The study is based on ecological data Data was collected from so may not reflect more recent trends in oral health Little as the USA situation is markedly different from New Zealand. 102

103 Appendix 4: Toxicology and Pharmacology [42] Review Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Proteomic analysis of brain proteins of rats exposed to high fluoride and low iodine Yaming Ge, Ruiyan Niu, JianhaiZhang, Jundong Wang Archives of Toxicology Toxicology Proteomic analyses were used to compare the profile of brain proteins in four different groups of rats. The subjects were 20 day old animals which both as fetuses and newborns had fallen into one of four exposure group depending on their fluoride and iodine intakes. Thus there were high F (HF), low I (LI), high F plus low I (HFLI), and control groups (the latter having low F and normal I). The high F groups received fluoride in drinking water at a level of 100 mg/l. Five proteins were identified whose regulation was altered at least five fold more relative to the control group. These were guanine nucleotide-binding protein, adenylosuccinate lyase, lactic dehydrogenase, proteosome alpha3, and synaptotagmin. These proteins are mainly involved in cellular signalling, energy generating metabolism, and protein metabolism. Little comparison was made between the HF, LI, and HFLI groups; comparisons being limited to the control group. Location of Study: Time of Study: Type of Study: Study Validity: Key Points: Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: China c Experimental Low FAIR FAIR FAIR FAIR Limitations: It is difficult to assess what the implications are from this study s findings, not least because the high fluoride groups received fluoride in drinking water at the very high level of 100 mg/l. Also, no attempt was made to assess the actual doses of fluoride or iodine received, only the levels in the diet and drinking water. The clinical relevance of the observed differences in proteonomics between the study groups is also not very 103

104 Can the findings be generalised? No clear. Also the potential contribution of low iodine as opposed to high fluoride intakes was not examined. Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: No None 104

105 [43] Review Date: September/ October 2011 Study Identification: Title: Increased level of apoptosis in rat brains and SH-SY5Y cells exposed to excessive fluoride- a mechanism connected with activating JNK phosphorylation. Yan-Jie Liu, Zhi-Zhong Guan, Qin Gao, Jin-Jing Pei Authors: Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Toxicology letters Toxicology JNKs (c-jun N-terminal kinases) are potent effectors of neuronal death and neuroinflammation, and regulators for the apoptotic ( programmed cell death ) process. Animals developing fluorosis from high fluoride intake have been noted to have increased signs of apoptosis. Animals were divided into three groups depending on the levels of fluoride in their drinking water (50ppm, 5ppm, <0.5ppm). It was investigated whether excessive fluoride caused apoptosis and whether this was related to activation of JNKs. Location of Study: Time of Study: Type of Study: Study validity: The data indicated that over-exposure to excessive fluoride could activate the JNK pathway, and many other data suggest that apoptosis is related to activation of this pathway. More specifically, apoptosis may be stimulated by phosphorylation of JNK induced by high F levels. All rats exposed to 50ppm for 6 months had some signs of dental fluorosis as did almost all of the 5ppm group though somewhat milder. China Not stated Experimental Key Points: Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: NO FAIR FAIR NO NO Limitations: Can the findings be generalised? NO One limitation was the selection of 5ppm F as the low level (which was sufficient to induce dental fluorosis in 11 of 12 of the animals) rather than say 1ppm F. Also the actual F doses were unknown as amount of water consumed not recorded. The study focussed on elucidating mechanisms rather than assessing risk. 105

106 Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 106

107 [44] Review Date: November 2011 Study Identification: Title: Reduction in fluoride-induced genotoxicity in mouse bone marrow cells after substituting high fluoride-containing water with safe drinking water Podder S, Chattopadhyay A, Bhattacharya S Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Journal of Applied Toxicology Toxicology The potential genotoxicity of fluoride was investigated by examining some markers of genetic damage in different groups of mice. Apart from the control group (Group 1), four groups of mice received 15mg/L of NaF (6.8mg/L as F) in drinking water for 30 days. Then, in three of these groups, this level was replaced with safe levels (0.1mg/L) of F, for 7 days, 30 days, or 90 days (in Groups 3,4 & 5 respectively), before investigations were undertaken. This enabled testing for both the effects of 15mg/L per se (Group 2) and for any reversibility of toxic effects over time. There was an increased percentage of dead cells in bone marrow in groups 2, 3, & 4 relative to controls. A significant suppression of mitotic index was noted in Group 3 animals relative to controls. Significant rises in the percentages of aberrant cells with chromatin breaks were also found in groups 2, 3, 4, and 5 relative to controls. However chromosomal aberrations were significantly reduced in those groups (4 and 5) receiving safe drinking water for 30 or 90 days respectively after their initial 30 days of 15mg/L NaF. This suggested some reversibility of effect. However it was not possible to conclude whether this reduction was due to repair of induced cellular damage or replacement of damaged cells by new cell populations. Location of Study: Time of Study: Type of Study: Study Validity: Key Points: Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? It was concluded that further study is required to resolve whether the disturbance in DNA repair mechanisms is a contributing factor in the results noted. The authors suggested that provision of safe (very low fluoride) drinking water as replacement for high fluoride levels could reduce F induced genotoxicity. India c Experimental FAIR 107

108 The study reaches valid conclusions with respect to the initial hypothesis/aim? Strengths: The inclusion of three groups receiving low fluoride water for various durations after their 30 days on high fluoride water provides the opportunity to assess the reversibility of the F effects. Limitations: There are significant limits to the study s generalisability as it only compares the effects of 15mg/L NaF (6.8 mg/l F) with 0.1mg/L F; that is, no comparison with levels around 1mg/L are made. Can the findings be generalised? NO Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NONE 108

109 [45] Review Date: September/ October 2011 Study Identification: Title: Authors Journal: Year: Volume: Pages: Area (label): Summary of Study: Abstract: Apoptosis of peripheral blood mononuclear cells in children exposed to arsenic and fluoride Rocha-Amador DO, et al. Environmental Toxicology and Pharmacology Toxicology Children living in an area with high fluoride and arsenic drinking water levels were compared to those in an area with low drinking water levels of F and As. Comparison includes assessing the levels of apoptosis in peripheral monocytes in children from the two areas. In the non-contaminated area (SGS), mean drinking water (DW) concentrations were 6.71ug/L for As and 0.67 for F. In the contaminated area (5 de Febrero), DW levels were 157.9ug/L for As and 8.19 for F. This marked difference was reflected in the respective mean urinary levels; for arsenic 14.2 versus 46.3ug/g creatinine, and for fluoride 1.94 versus 5.7ug/g creatinine. The frequency of apoptosis in peripheral monocytes was substantially higher in 5 de Febrero. A positive correlation was found between exposure levels and the level of apoptoses. About 95% of the children in 5 de Febrero had urinary fluoride levels higher than 2.0ug/g creatinine; this being the upper level previously found to be reached by subjects living in areas with F DWFCs less than 1mg/L. However the effect of arsenic may be more significant than fluoride with respect to induction of apoptosis. This can occur in vitro at arsenic concentrations as low as 5milimolar (mm). Arsenic has been reported to cause cell death in many malignant cells through apoptosis induction. Location of Study: Time of Study: Type of Study: Fluoride induced apoptosis has been observed in in vitro studies but effects in immune system cells in humans is inconsistent. Also the difference in frequency of apoptosis between the two populations was relatively small, and arsenic was thought the more significant factor. The authors considered the significance of their data was uncertain. Mexico 2011 Experimental Key Points: Evaluation Criterion: The aim/ hypothesis of the study are clearly stated? The study method is appropriate? Data collection quality? Sound logic is used in the conclusions reached? The study reaches valid NO FAIR NO 109

110 conclusions with respect to the initial hypothesis/aim? Strengths: NO Limitations: The study was constrained by the fact that the groups differed not only with respect to their fluoride exposures, but also their arsenic exposures. Also the clinical significance of the relatively small difference in apoptosis between the two groups is uncertain. Can the findings be generalised? Are the findings applicable to water fluoridation in New Zealand? Implications for the Ministry of Health water fluoridation policy: NO NO None 110

111 Appendix 5: Dean s Index 16 Dean s Fluorosis Index: Developed in the 1930s by H.T. Dean to assess the prevalence and severity of dental fluorosis in various communities in the United States. Major criteria for each category are listed below: Unaffected: The enamel is translucent. The surface of the tooth is smooth, glossy, and usually has a pale creamy white colour. Questionable: The enamel shows slight changes ranging from a few white flecks to occasional white spots. This classification is utilized in those instances in which a definitive determination of the mildest form of fluorosis is not warranted and a classification of unaffected is not justified. Very mild: Small opaque paper-white areas are scattered over the tooth surface, but do not involve as much as 25% of the surface. Mild: White opaque areas on the surface are more extensive, but do not involve as much as 50% of the surface. Moderate: White opaque areas affect more than 50% of the enamel surface. Severe: All enamel surfaces are affected. The major aspect of this classification is the presence of discrete or confluent pitting. 16 Source: Centre for Disease Control (CDC), USA: 111

112 Appendix 6: The Significant Caries (SiC) Index 17 The SiC Index was introduced by the World Health Organisation (WHO) in 1981 to address the issue of skewed caries prevalence in many countries. It was found that mean DMFT did not accurately reflect oral health where distribution of caries was skewed, i.e. a subgroup had a high DMFT in a population where many were caries free. The SIC focuses attention on individuals with the highest caries prevalence in a population. It is calculated by: 1. Sorting individuals in a study population by DMFT 2. Selecting the top 1/3 of the study population 3. The mean DMFT for this subgroup is calculated and this forms the SiC Index Example: The graph shows caries data for a population, expressed as frequency distribution. In this example, about 45% are caries free (DMFT = 0). The mean DMFT is 1.91, and the Significant Caries Index is Arrow and vertical line indicate the individuals that are included in the calculation of the index. 17 Source: Oral Health Database, Malmo University, Sweden: 112